In a statement, the ministry said the attack, perpetrated by an unknown assailant, left five dead and 40 others injured.
“The local police have confirmed they are currently treating the incident as a terrorist incident,” it said.
The attacker mowed pedestrians as he drove across Westminster Bridge, hitting and injuring members of the public along the way.
Three off duty police officers were also among those injured on the Bridge.
The car came to a stop when it crashed into the railings near the Houses of Parliament.
The attacker then tried to enter the building, stabbing a police officer and attempting to attack another before he was gunned down.
“The High Commission of Malaysia in London is in close contact with the local authorities and currently providing timely updates to the Malaysian community in the city over the incident,” it said.
The Ministry of Foreign Affairs conveyed its deepest sympathies and condolences to the families of the victims of the incident.