The PM has called the attack a “tragic and cowardly act”, describing it as an “act of terror”.
“This is one of the most shocking acts of terrorism we have seen in our time,” he said in a statement.
British Prime Minister Theresa May called the attackers “cowards” and urged them to “stop their barbaric acts”. “
I call on the British people to stand united and to work together as one nation to defeat terrorism and protect the innocent and the vulnerable.”
British Prime Minister Theresa May called the attackers “cowards” and urged them to “stop their barbaric acts”.
The attack happened in central London and is thought to have been carried out by two men who police believe are foreign fighters.
The attack comes as the UK prepares to leave the EU and a new poll shows more than half of people are against Britain joining the bloc.
More: BBC News: Britain is not joining the EU because of Brexit The attackers have been described as Asian in appearance, but were wearing full-face veils.
“These are not people who have been training or living in this country for a very long time,” Mr Cameron said.
“They have come from a land of violence and chaos, and we will not be part of that.”
He said he was deeply saddened by the attack and called for a “united, peaceful, and prosperous” Britain.
“This was a brutal attack, which has left the innocent people of Britain and all of us deeply saddened and shocked,” he added.
Police have been on high alert in London and the capital after a wave of terror attacks in the US, Europe and Britain, and British police have carried out a nationwide manhunt.
The attacker who carried out the attack is still at large, and Mr Cameron was urged to “continue to show courage and show strength”.
The BBC’s David Willey says that even before the attack, London’s streets were full of people who had not been in a panic, saying “there is no reason for this to happen” despite the terror alert level being raised to “severe”.
“There is no justification for this,” he says.
“The police are working very hard to get to the man. “
We’re getting closer to him.” “
The police are working very hard to get to the man.
We’re getting closer to him.”
Mr Cameron has described the attack as “cowardly and cowardly”, and he urged the public to “stand united and work together”.
“Londoners are resilient,” he told the House of Commons.
More: UK’s PM on the attack: “This isn’t about us” BBC News correspondent James Reynolds reports from London, where thousands have turned out to support Mr Cameron. “
And I call on our friends in the other nations of the world to join us in a united, peaceful and prosperous Britain.”
More: UK’s PM on the attack: “This isn’t about us” BBC News correspondent James Reynolds reports from London, where thousands have turned out to support Mr Cameron.
The British prime minister also appealed for anyone with information to come forward. “
As a nation, we will stand together and work with our allies, to build a united and prosperous society.”
The British prime minister also appealed for anyone with information to come forward.
“If you have information that might help us understand what happened, please contact us at police.uk or call the emergency line on 0800 555 111,” he wrote on Twitter.
Police said they had no information to suggest the attackers were linked to any terror organisation.
The UK is currently negotiating a divorce with the EU, but the UK’s withdrawal could still be postponed if the talks fail.
A number of US cities have already imposed new restrictions on people entering the UK, including New York and Chicago.
Earlier in the day, the US President Donald Trump tweeted his support for the British prime Minister.
“God bless you, Sir,” he tweeted.
“What a great country we have here, so many wonderful people, so much history, so wonderful people.
I know what it’s like to be scared by people from another country.
I think we should stay and be proud of it.”
A man was arrested on suspicion of terror offences after the attack