The former home secretary was seen wiping away tears as she listened to speeches in the crowd at a pro-Israel event in Trafalgar Square, central London.
Wearing a blue coat and a grey beanie, she told reporters that the remaining hostages caught up in the conflict in the Middle East need to be brought home “now”.
“I’m here to stand in solidarity with Israel,” she said. “It has been 100 days since innocent people have been taken hostage by the Hamas terrorists and we need to bring them home now. Bring them home now.”
Ms Braverman has been a vocal critic of the pro-Palestine marches that have filled London’s streets over recent months, but this is the first time she has been seen at a pro-Israel event since she left the Cabinet.
Around 25,000 people gathered in cold temperatures on Sunday afternoon for the Trafalgar Square rally, which condemned the proscribed terror group Hamas’s invasion of Israel on Oct 7, leaving more than 1,400 people dead and 200 taken hostage.
Many carried Israeli flags and held pictures of some of the 105 people still believed to be being held captive.
Isaac Herzog, Israel’s president, told the rally via video link that “this battle belongs to the whole free world”, adding: “In the face of those who wish to scare us into silence, you’ve stood up and spoken out with clarity, pride, and passion.”
Meanwhile, a 24-hour rally is being held in the Israeli city of Tel Aviv.
The London gathering comes a day after a pro-Palestine demonstration in the city, in which at least six people were arrested.
Some at the latest pro-Palestine march appeared to chant support for Iran-backed Houthi rebel attacks on commercial shipping, shouting “Yemen, Yemen make us proud, turn another ship around” in apparent celebration of the escalation of the conflict.
Israel is under pressure over civilian deaths in Gaza, where it is waging a major military operation aiming to wipe out Hamas, with more than 9,300 civilians estimated to have been killed and 3,600 injured.
One of the speakers at the Israel rally on Sunday was the Tory Lord Pickles, the UK’s special envoy for post-Holocaust issues, who told the crowd: “I’ve met many Holocaust survivors and I never understood why in the 1930s nobody did anything about the Nazis.
“By midday on Oct 7 I understood. The world is wonderful at remembering not-long-dead Jews but when the Jews seek to defend themselves the world is indifferent.”
British-Israeli Eylon Levy, the state of Israel’s English language spokesman, told the rally: “100 days after Oct 7, one day after another hate parade in London we stand here outnumbered and outmanned yet unafraid and united.”