The Queen has given a statement after the terror attack
The Queen has said her "thoughts, prayers, and deepest sympathy" are with all those who have been affected by yesterday's "awful violence".
Three people were killed and a terror attacker shot dead after the attack in Westminster on Wednesday.
The assailant, who has not been named by police, drove a 4×4 over Westminster Birdge hitting tourists and causing mass panic.
He then crashed the rented car into a barrier outside Parliament and ran with a knife towards police officers.
Armed police rush toward Parliament after colleague stabbed
PC Keith Palmer was stabbed to death and two colleagues were injured.
Seven people remain in a critical condition in hospital.
Theresa May has also paid tribute to the victims.
The Prime Minister said Parliament was sending out the message following Wednesday's attack by a knife-wielding terrorist that "we will never waver in the face of terrorism".
An hour after MPs gathered at the usual time and stood for a minute's silence in honour of the innocent people killed in the attack, Mrs May said the actions of millions around the country showed terrorists "we will never give in".
In a show of defiance, the PM told a packed Commons chamber: "The greatest response lies not in the words of politicians, but in the everyday actions of ordinary people.
"For beyond these walls today, in scenes repeated in towns and cities across the country, millions of people are going about their days and getting on with their lives.
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London Terror Attack: LATEST PICTURES Thu, March 23, 2017
5 dead and 40 injured in Westminster terror attack
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Police forensic officers in Parliament Square outside the Houses of Parliament in London, after seven people were arrested in raids in London, Birmingham and elsewhere linked to the Westminster terror attack
A response that says to the men and women who propagate this hate and evil 'You will not defeat us'
"The streets are as busy as ever, the offices full, the coffee shops and cafes bustling.
"As I speak, millions will be boarding planes and aeroplanes to travel to London and to see for themselves the greatest city on Earth.
"It is in these actions – millions of acts of normality – that we find the best response to terrorism.
"A response that denies our enemies their victory, that refuses to let them win, that shows we will never give in.
"A response driven by that same spirit that drove a husband and father to put himself between us and our attacker and to pay the ultimate price.
"A response that says to the men and women who propagate this hate and evil 'You will not defeat us'.
"Mr Speaker, let this be the message from this House and this nation today. Our values will prevail."
Theresa May defiant in Parliament after Westminster attacked