Prime Minister Boris Johnson on Sunday said there was no place for anti-Semitism in society and that British Jews should not have to endure "shameful racism".
"There is no place for antisemitism in our society," Johnson said on Twitter.
"Ahead of Shavuot, I stand with Britain’s Jews who should not have to endure the type of shameful racism we have seen today."
Johnson did not specify what incident he was referring to.
A video posted online earlier on Sunday showed a convoy of cars bearing Palestinian flags driving through north London and broadcasting anti-Semitic messages from a megaphone.
Reuters has not been able to independently verify the video or when it was filmed.
Britain's Metropolitan police said: "We are aware of a video appearing to show anti-Semitic language being shouted from a convoy of cars in the St John's Wood area this afternoon.
"Officers are carrying out urgent enquiries to identify those responsible. This sort of behaviour will not be tolerated."
