The participants, made up mainly of London-based Muslims, left-wing activists, ultra-Orthodox Jews and members of the Neturei Karta movement, waved Palestinian flags and chanted "Free, free Palestine" and "End the occupation" as they walked from outside the BBC building in Duchess Street to Grosvenor Square.
Some of the protesters held banners accusing Israel of genocide such as "Stop ethnic cleansing. Israel destroys three homes every two days."
At various stages on the route, demonstrators encountered clutches of Israeli supporters, mostly members of the local Jewish and Israeli community, with police trying to move them out of the way so that the main march could continue.
London Mayor Sadiq Khan had been called on by Israel advocates to cancel the march, due to concerns that it propagates displays of antisemitism and terrorism. About 23,000 people signed a petition to have the event banned, claiming that Khan must live up to his campaign pledges to eradicate extremism and anti-Semitism.
"After the terrible recent terrorist events in Manchester and London this display of extremism has no place on the streets of the UK," the petition stated.
However, last week the mayor told members of the British Jewish community that he lacked the authority to fulfil the demand.