Activists calling for an arms embargo on Israel have sprayed Labour’s headquarters with red paint.
Demonstrators from the Youth Demand group insisted both the Government and Opposition should commit to preventing the supply of weapons to the country as they targeted the party’s offices in central London.
Labour has said arms exports to Israel should be suspended if ministers have received legal advice that it has breached international law, but has resisted backing an embargo without seeing the guidance.
The Government has come under increased pressure in recent days to publish the advice it has been given following an attack which killed seven aid workers in Gaza, including three Britons.
Youth Demand, which is calling for an arms embargo as well as an end to oil and gas drilling in the North Sea, said three of its supporters had sprayed the outside of Labour’s head office while another painted the lobby.
One of those involved, Chris Faulkner, 21, an earth sciences student from Oxford, said: “There has never been a safer time for Labour to be bold. Instead, they are behaving like the biggest cowards imaginable.
“Young people will not stand by and watch Keir Starmer allow mass murder by selling weapons to Israel and allowing the development of new oil and gas.
“Over 30,000 people have been killed in Gaza and the breakdown of our climate will kill hundreds of millions more in the coming decades.”
Labour declined to comment.
Youth Demand later claimed 11 people had been arrested in connection with the incident.
Scotland Yard has been contacted for comment.
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