A minute's silence will be held across the UK at midday to remember the 38 people - including 30 Britons - killed in the Tunisia beach attack a week ago.
Flags will be flown at half-mast over Whitehall and Buckingham Palace, while play at Wimbledon will be delayed.
The Queen and Prime Minister David Cameron will join the silence.
The first inquests into the deaths of the Britons will begin later, with the bodies of more of the dead expected to arrive back at RAF Brize Norton.
The foreign secretary has said all 30 British people killed have been identified. Philip Hammond said he was confident the figure was the final British death toll from the beach shootings in Sousse last Friday.
The Queen and Duke of Edinburgh will join staff in marking the silence at the University of Strathclyde during an official visit to open a new technology and innovation centre, while Mr Cameron will be in his Witney constituency in Oxfordshire.
A number of mosques are expected to participate in the silence, and many will also remember the victims during Friday prayers.
Police officers across the country will take part, the National Police Chiefs Council said.
And a special ceremony will also be held at the scene of the killings in Sousse, where dignitaries and tourists are expected to attend.
At Wimbledon, matches on the outdoor courts usually start at 11:30 BST but will begin at 12:15 to allow spectators and participants to take part in the silence.
Tunisia attack: Minute's silence to be held for victims
BBC News
3 July 2015
The bodies of more of the British victims are expected to be brought back to the UK by the RAF today
A minute's silence will be held across the UK at midday to remember the 38 people - including 30 Britons - killed in the Tunisia beach attack a week ago.
Flags will be flown at half-mast over Whitehall and Buckingham Palace, while play at Wimbledon will be delayed.
The Queen and Prime Minister David Cameron will join the silence.
The first inquests into the deaths of the Britons will begin later, with the bodies of more of the dead expected to arrive back at RAF Brize Norton.
The foreign secretary has said all 30 British people killed have been identified. Philip Hammond said he was confident the figure was the final British death toll from the beach shootings in Sousse last Friday.
Tributes have been left at the scene of the attack, where a ceremony will take place
The Queen and Duke of Edinburgh will join staff in marking the silence at the University of Strathclyde during an official visit to open a new technology and innovation centre, while Mr Cameron will be in his Witney constituency in Oxfordshire.
A number of mosques are expected to participate in the silence, and many will also remember the victims during Friday prayers.
Police officers across the country will take part, the National Police Chiefs Council said.
And a special ceremony will also be held at the scene of the killings in Sousse, where dignitaries and tourists are expected to attend.
At Wimbledon, matches on the outdoor courts usually start at 11:30 BST but will begin at 12:15 to allow spectators and participants to take part in the silence.
The Queen and Duke of Edinburgh will join staff in marking the silence at the University of Strathclyde in Glasgow during an official visit to open a new technology and innovation centre
What we know about the British victims
Bodies returned
Later, the first inquests will open at West London Coroner's Court. Coroner Chinyere Inyama is expected to open and adjourn the hearings.
Further inquests are due to be opened at the court on Saturday and Sunday.
Post-mortem examinations will be carried out before the bodies are released to their families.
The bodies of 17 of the British victims have now been returned to the UK.
The repatriation of the dead is likely to take several days, with two further flights planned for Friday and Saturday.
The Foreign Office has now confirmed the deaths of Angie and Ray Fisher, aged 69 and 75 respectively, who were from Leicester and had been missing.
Thomson and First Choice has said all 30 British people killed were its customers.
"The whole company would like to extend our deepest sympathies to the family and friends of those involved in this tragic event," it added.
"Our main focus now is to ensure the families of the deceased and our customers who have been injured receive all possible support at this incredibly difficult time."
A Tunisian man who witnessed the attack described to BBC correspondent Ben Brown how he tried to help tourists
Other victims killed in the attack include three Irish citizens, two Germans, one Belgian, one Portuguese and one Russian national.
BBC correspondent Ben Brown, who is in Sousse, spoke to one Tunisian man who witnessed the attack and helped tourists to safety.
He said he feared for his life but when he realised the gunman was not interested in shooting Tunisians he linked arms with other local people to try to form a human barrier along the beach.
"You could only see one colour," he said. "Everywhere was red."
"I feel I could have done more. I tried my best... He is not Tunisian. We are not like that."
He also pleaded with tourists not to abandon Tunisa. "Please keep coming. Don't let him win," he said.
Background and analysis
What we know so far
Special report on the Tunisia attack
Who was the gunman?
Why was Tunisia targeted?
How do terrorist attacks affect tourism?
Tributes have been paid to victims in England, Wales, Scotland and Northern Ireland
What can UK police do?
'Tragic event'
Tunisian authorities have identified 28-year-old student Seifeddine Rezgui as the gunman who carried out the attack.
They are also holding eight suspects in custody on suspicion of being directly linked to the attack, which jihadist group Islamic State (IS) has claimed. Four others who were held have been released.
On Thursday, Defence Secretary Michael Fallon set out the case for air strikes on IS targets in Syria in Parliament.
He has suggested the Tunisia attack may have been planned by IS in Syria.
Meanwhile, the Metropolitan Police has said more than 160 officers were interviewing witnesses to the attack who had returned to the UK.
A total of 20 officers have been sent to Tunisia by the Met's Counter Terrorism Command, which is leading the coroner's investigation.
The National Policing Counter Terrorism Headquarters has also sent specialist security advisers to Tunisia, to support a review of security at resorts and tourist attractions.
Scotland Yard has previously said its investigation into the attack is likely to be one of the largest counter-terrorism deployments since the London 7/7 bombings in 2005, which killed 52.
Tunisia: National Silence News Special showing coverage of the minute's silence will be broadcast online and on BBC One and the BBC News Channel at 11:45 BST.
Tunisia attack: Minute's silence to be held for victims - BBC News
Flags will be flown at half-mast over Whitehall and Buckingham Palace, while play at Wimbledon will be delayed.
The Queen and Prime Minister David Cameron will join the silence.
The first inquests into the deaths of the Britons will begin later, with the bodies of more of the dead expected to arrive back at RAF Brize Norton.
The foreign secretary has said all 30 British people killed have been identified. Philip Hammond said he was confident the figure was the final British death toll from the beach shootings in Sousse last Friday.
The Queen and Duke of Edinburgh will join staff in marking the silence at the University of Strathclyde during an official visit to open a new technology and innovation centre, while Mr Cameron will be in his Witney constituency in Oxfordshire.
A number of mosques are expected to participate in the silence, and many will also remember the victims during Friday prayers.
Police officers across the country will take part, the National Police Chiefs Council said.
And a special ceremony will also be held at the scene of the killings in Sousse, where dignitaries and tourists are expected to attend.
At Wimbledon, matches on the outdoor courts usually start at 11:30 BST but will begin at 12:15 to allow spectators and participants to take part in the silence.
Tunisia attack: Minute's silence to be held for victims
BBC News
3 July 2015
The bodies of more of the British victims are expected to be brought back to the UK by the RAF today
A minute's silence will be held across the UK at midday to remember the 38 people - including 30 Britons - killed in the Tunisia beach attack a week ago.
Flags will be flown at half-mast over Whitehall and Buckingham Palace, while play at Wimbledon will be delayed.
The Queen and Prime Minister David Cameron will join the silence.
The first inquests into the deaths of the Britons will begin later, with the bodies of more of the dead expected to arrive back at RAF Brize Norton.
The foreign secretary has said all 30 British people killed have been identified. Philip Hammond said he was confident the figure was the final British death toll from the beach shootings in Sousse last Friday.
Tributes have been left at the scene of the attack, where a ceremony will take place
The Queen and Duke of Edinburgh will join staff in marking the silence at the University of Strathclyde during an official visit to open a new technology and innovation centre, while Mr Cameron will be in his Witney constituency in Oxfordshire.
A number of mosques are expected to participate in the silence, and many will also remember the victims during Friday prayers.
Police officers across the country will take part, the National Police Chiefs Council said.
And a special ceremony will also be held at the scene of the killings in Sousse, where dignitaries and tourists are expected to attend.
At Wimbledon, matches on the outdoor courts usually start at 11:30 BST but will begin at 12:15 to allow spectators and participants to take part in the silence.
The Queen and Duke of Edinburgh will join staff in marking the silence at the University of Strathclyde in Glasgow during an official visit to open a new technology and innovation centre
What we know about the British victims
Bodies returned
Later, the first inquests will open at West London Coroner's Court. Coroner Chinyere Inyama is expected to open and adjourn the hearings.
Further inquests are due to be opened at the court on Saturday and Sunday.
Post-mortem examinations will be carried out before the bodies are released to their families.
The bodies of 17 of the British victims have now been returned to the UK.
The repatriation of the dead is likely to take several days, with two further flights planned for Friday and Saturday.
The Foreign Office has now confirmed the deaths of Angie and Ray Fisher, aged 69 and 75 respectively, who were from Leicester and had been missing.
Thomson and First Choice has said all 30 British people killed were its customers.
"The whole company would like to extend our deepest sympathies to the family and friends of those involved in this tragic event," it added.
"Our main focus now is to ensure the families of the deceased and our customers who have been injured receive all possible support at this incredibly difficult time."
A Tunisian man who witnessed the attack described to BBC correspondent Ben Brown how he tried to help tourists
Other victims killed in the attack include three Irish citizens, two Germans, one Belgian, one Portuguese and one Russian national.
BBC correspondent Ben Brown, who is in Sousse, spoke to one Tunisian man who witnessed the attack and helped tourists to safety.
He said he feared for his life but when he realised the gunman was not interested in shooting Tunisians he linked arms with other local people to try to form a human barrier along the beach.
"You could only see one colour," he said. "Everywhere was red."
"I feel I could have done more. I tried my best... He is not Tunisian. We are not like that."
He also pleaded with tourists not to abandon Tunisa. "Please keep coming. Don't let him win," he said.
Background and analysis
What we know so far
Special report on the Tunisia attack
Who was the gunman?
Why was Tunisia targeted?
How do terrorist attacks affect tourism?
Tributes have been paid to victims in England, Wales, Scotland and Northern Ireland
What can UK police do?
'Tragic event'
Tunisian authorities have identified 28-year-old student Seifeddine Rezgui as the gunman who carried out the attack.
They are also holding eight suspects in custody on suspicion of being directly linked to the attack, which jihadist group Islamic State (IS) has claimed. Four others who were held have been released.
On Thursday, Defence Secretary Michael Fallon set out the case for air strikes on IS targets in Syria in Parliament.
He has suggested the Tunisia attack may have been planned by IS in Syria.
Meanwhile, the Metropolitan Police has said more than 160 officers were interviewing witnesses to the attack who had returned to the UK.
A total of 20 officers have been sent to Tunisia by the Met's Counter Terrorism Command, which is leading the coroner's investigation.
The National Policing Counter Terrorism Headquarters has also sent specialist security advisers to Tunisia, to support a review of security at resorts and tourist attractions.
Scotland Yard has previously said its investigation into the attack is likely to be one of the largest counter-terrorism deployments since the London 7/7 bombings in 2005, which killed 52.
Tunisia: National Silence News Special showing coverage of the minute's silence will be broadcast online and on BBC One and the BBC News Channel at 11:45 BST.
Tunisia attack: Minute's silence to be held for victims - BBC News
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