Thousands of pro-Palestinian protesters have marched through central London – a day after the UK joined the US in attacking Houthi bases in Yemen.
The Iran-backed rebel group, which supports Hamas, has been targeting commercial shipping in the Red Sea.
It has vowed to damage vessels it believes are heading to and from Israel until there is a ceasefire in Gaza.
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One speaker in Parliament Square on Saturday said British planes had been “flying where they do not belong”.
A few Yemeni flags were spotted on the march, Sky News correspondent Ivor Bennett said.
One flag read “Hands off Yemen”. According to its bearer, the only way to stop Houthi attacks on shipping in the Red Sea is to support a ceasefire in Gaza.
The protesters want Israel to stop its military operations in Gaza, which followed the Hamas attacks in Israel on 7 October.
Husam Zomlot, the Palestinian ambassador to the UK, accused the British government of “complicity” with Israel.
Speaking in Parliament Square, he said Palestine was a “nation of freedom fighters”, adding: “I stand before you with a broken heart but not a broken spirit.”
He also congratulated South Africa for bringing a genocide case against Israel at the UN’s International Court of Justice.
Mary Lou McDonald, the president of Sinn Fein, told the crowd that a better situation for the Palestinian people is possible.
“When I say this, standing in London, in common cause with you, (having) walked our own journey out of conflict, building peace for 25 years, this can happen,” she said.
“This must happen and we will ensure that it does.”
Former Labour leader Jeremy Corbyn addressed protesters in Parliament Square, while his former shadow chancellor, John McDonnell, could be seen leading the march as it left Bank.
A “significant policing presence” of about 1,700 officers was planned by the Metropolitan Police, which has been handing out leaflets.
There are restrictions, including: any person participating must not deviate from the specified route; the speeches must end by 4.30pm; the whole event must end by 5pm.
No participant in the protest may enter the area around the Israeli Embassy.
James Cleverly, the home secretary, said he had been briefed by Met commissioner Sir Mark Rowley on plans to “ensure order and safety” during the protest.
“I back them to use their powers to manage the protest and crack down on any criminality,” he said.