Cars could be banned from Parliament Square following a suspected terrorist attack on Tuesday morning, according to the Metropolitan Police Commissioner.
Cressida Dick said pedestrianising parts of Parliament Square would help stop further vehicle terrorist attacks. She described vehicles as the "weapon of choice" for terrorists.
After the incident, 29-year-old UK national Salih Khater was arrested on suspicion of preparing an act of terror, and for attempted murder.
The car involved, a Ford Fiesta, was driven from Birmingham to London late on Monday, before spending several hours in the Tottenham Court Road area. It was then driven around Westminster for an hour and a half, before being ploughed into a security barrier near the House of Lords, just before 7.40am.
Ms Dick said: "You will notice that the security around Parliament both in terms of armed officers and police officers and physical barriers has been further enhanced over the last several months and there is more to come on that in further months.
"Whether that area outside should be pedestrianised further, there should be further physical works done, I think is a matter that will be discussed no doubt between parliamentary authorities, us, the intelligence agencies and indeed the local authorities and the mayor."
The UK's most senior officer praised the courage of police at the scene, who responded quickly.
As part of the investigation into the attack, police searched two properties in Birmingham and one in Nottingham.
At the time of writing, the suspect is not co-operating with officers, according to the Metropolitan Police’s counter-terrorism head, Neil Basu.