Tens of thousands of protesters will assemble near Hyde Park at midday on Saturday.
Rishi Sunak accepts that the march will go ahead after meeting with Met Police chief.
Protesters accuse the prime minister of stoking fear.
The route for a pro-Palestinian march taking place in central London on Armistice Day has been revealed.
The latest protest organised by the Palestine Solidarity Campaign (PSC) will go ahead despite being heavily criticised by Rishi Sunak, who branded it "provocative and disrespectful" and claimed there was a risk to war memorials.
The prime minister has since accepted that the Ceasefire Now March for Palestine will happen after meeting Met Police commissioner Sir Mark Rowley to discuss the issue on Wednesday.
The PSC has confirmed protesters will assemble near Hyde Park at midday on 11 November and march across Vauxhall Bridge to the US embassy.
The protest will stay well clear of the Cenotaph in Whitehall.
The PSC has accused the prime minister of provoking alarm over the protest this weekend.
The group wrote on X: "The government is stoking up fears and playing politics when most British people support a #ceasefireNOW to prevent more indiscriminate killing of civilians in Gaza, including 4,500 children. We won't be deflected by their deeply irresponsible comments. See you Saturday in London."
Union chief Mick Lynch vows to join pro-Palestine march (Yahoo News UK)
Meanwhile, Sunak has come under pressure to sack home secretary Braverman after she defied Downing Street by publishing an article accusing police of bias over protests in support of Palestine.
No 10 said they were "investigating" after it was understood the article was submitted to Downing Street, but did not get signed off as significant alterations were requested. The piece was published nonetheless.
Labour mocked the prime minister as “spineless” and argued that the move by Braverman amounts to a breach of the ministerial code.
The marches calling for a ceasefire come after Hamas said the death toll in Gaza had reached 10,000, including 4,000 children, since the violence escalated after it killed more than 1,400 Israelis during the 7 October attacks.