Tensions in the Middle East bubbled up in New York City Monday, where hundreds of pro-Palestinian demonstrators gathered to denounce the Israeli government and demand that the United States stop its support, while supporters of Israel convened for their own counter-protests and prayers.

With signs reading "Israel go to hell!" and "NYC stands with Gaza," people of all ages stood in front of the Israeli consulate general waving Palestinian flags.

At Israel's Ramla military base, civilian volunteers and reservists gather in a show of unity that comes after nearly a year of unprecedented political division in the nation.

A surprise assault launched by the Palestinian militant group Hamas over the weekend has killed hundreds in Israel but also precipitated mass mobilisation among Israelis who have found a renewed dedication to their national cause.

The shock of a Hamas assault has restored the United States to a familiar role as unequivocal backer of Israel, using its leverage not to encourage calm but to shield its ally.

Prime Minister Benjamin Netanyahu has historically had rocky relations with Democratic presidents such as Joe Biden over the Israeli leader's opposition to Palestinian sovereignty and engagement with Iran and, most recently, his hard-right government's overhaul of the judiciary.

Colombia's President Gustavo Petro on Monday compared Israel's targeting of Gaza in retaliation for deadly attacks by militant group Hamas to the Nazi persecution of Jews.

Replying to a statement by Israeli Defense Minister Yoav Gallant announcing a "complete siege" of Gaza in a fight against "animals," Petro said: "This is what the Nazis said of the Jews."

Writing on X, formerly Twitter, the Colombian president added that "democratic peoples cannot allow Nazism to reestablish itself in international politics."

The usually bustling streets of Jerusalem were eerily quiet on Monday as deadly fighting between Israel and Palestinian militants raged for a third day in and around the Gaza Strip.

"Jerusalem is indeed a ghost town," said May Bahbah, a Palestinian resident of Jerusalem in her 40s.

"People are in fear and worried," she told AFP, standing next to a shuttered greengrocer.

Palestinians living in the city's Israeli-annexed east "have to go to their jobs but they are worried they might be abused" by Israeli forces "because of the war situation", said Bahbah.

Previous conflicts between Hamas and Israel have ended through mediation by powers with a keen interest in Middle East peace but the unprecedented nature of the assault by the Palestinian militant group could make any diplomatic efforts fruitless for now, analysts say.

Egypt, which has a peace treaty with Israel and also borders the Gaza Strip, a Hamas stronghold, has in the past repeatedly been called upon to act as mediator, with Cairo also happy to add to its diplomatic prestige.

Iran took the lead in celebrations following the surprise attack by Palestinian Islamist group Hamas on Tehran's arch-enemy Israel, even as it rejected accusations of direct involvement.

The Islamic republic's backing was made manifest by billboards installed in Tehran's major plazas, including Palestine Square.

"The great liberation has begun," proclaimed one while a second showed the black and white chequerboard of the Palestinian keffiyeh gradually subsuming the white and blue flag of Israel.

Inbal Reich Alon has fled to safety after 15 hours locked down in a shelter as Hamas militants stormed her Gaza border community, killing and kidnapping dozens of Israelis.

"We don't know whether we have somewhere to go back to," she told AFP on Monday at a Dead Sea hotel where she is now staying along with about 150 residents of Beeri, a kibbutz in Israel's south.

Scotland's First Minister Humza Yousaf on Monday said his wife's parents have been caught up in the aftermath of Hamas's weekend attack on Israel.

Yousaf's wife Nadia El-Nakla is Palestinian and her parents, who live in Dundee, northeast Scotland, were visiting family in Gaza.

"They've been in Gaza and are currently trapped in Gaza, I'm afraid," he told reporters.

Yousaf, who in March became the first Muslim leader of a government in western Europe, said the Israeli authorities had told his parents-in-law to leave but not guaranteed safe passage.

The UK government on Monday insisted that Rwanda is an appropriate place to deport failed asylum seekers, as it tried to overturn a court ruling that the policy is unlawful.

Three appeal court judges in London blocked the controversial plan in June, assessing that the African nation could not be considered a safe, third country.

At the start of a three-day hearing at the Supreme Court on Monday, lawyer James Eadie, representing the interior ministry, conceded that Rwanda was "a country less attractive" than the UK.