Thousands of demonstrators gathered in London on Sunday to stage a pro-Israel rally near the country's embassy in Kensington.
Protesters lined the streets and waved Israeli flags at the event, which was organised by the Zionist Federation and supported by 60 organisations. Observers estimated that a few thousand people attended.
Labour MP Louise Ellman addressed the crowds and called for an end to hostilities between Israel and the Palestinians.
"I've called on our government and supporters of both Israelis and Palestinians to work for a ceasefire," she said.
Alan Aziz, director of the Zionist Foundation, told the Jewish Chronicle: "It has been over half a century since Britain last experienced the sound of sirens warning of impending rocket fire.
"While the terror of the Blitz is thankfully just an historical fact for most Londoners, for ordinary Israelis it's an everyday reality. It is impossible to understand why Israel is targeting terrorists in Gaza without acknowledging this reality."
Vivian Wineman, president of the Board of Deputies of British Jews, said the protest was not about pitting Israelis against Palestinians, but addressing the "extremism and violence in the form of Hamas, which is the true enemy".
"It is a barbarous regime which slaughters women and children of nations with whom it is in conflict but also a regime which exposes its own people to violence," Wineman said. "It takes brutality and callousness to new and unprecedented levels."
Last week, pro-Israel demonstrators staged a rally in Los Angeles and clashed with Palestine supporters after protesters ripped a Palestinian flag away from a passing vehicle.
The Los Angeles County Sheriff's Department said in a news release that a "verbal and physical altercation ensued between the occupants of two vehicles leaving the area". KNBC reported that four people were arrested on suspicion of assault with a deadly weapon.