United States security officials, Rishi Sunak and other world leaders ...

The Palestinian militant group Hamas has launched the biggest attack on Israel in years in a surprise assault that combined gunmen crossing into several Israeli towns with a heavy barrage of rockets fired from the Gaza Strip.

Israel said it was on a war footing and began its strikes against Hamas targets in Gaza, with Israeli media reporting gunbattles between bands of Palestinian fighters and security forces in southern Israel.

Leaders from around the world have reacted to the attack.

Foreign Affairs Minister Penny Wong

"We call for these attacks to stop and recognise Israel's right to defend itself," she wrote on social media. 

"Australia urges the exercise of restraint and protection of civilian lives." 

White House National Security Council

White House National Security Council spokesperson Adrienne Watson said the US "unequivocally condemns" attacks by the Palestinian militant group Hamas against Israeli civilians and firmly stands with the government and people of Israel.

Citing a statement from the spokesperson, CNN reported that White House National Security Adviser Jake Sullivan had spoken with his Israeli counterpart, Tzachi Hanegbi, and would remain in close contact.

British Prime Minister Rishi Sunak

"I am shocked by this morning's attacks by Hamas terrorists against Israeli citizens. Israel has an absolute right to defend itself," Mr Sunak wrote on X, the social media platform formally known as Twitter. 

"We're in contact with Israeli authorities, and British nationals in Israel should follow travel advice."

Saudi Arabia's Foreign Ministry

The ministry called for an "immediate cessation of violence" between Israel and the Palestinians, the state news agency reported.

"We are following the unprecedented developments between a number of Palestinian factions and Israel occupation forces which has led to a high level of violence on a number of fronts".

Smoke rises following Israeli strikes in Gaza.(Reuters: Mohammed Salem)

Egyptian Foreign Ministry

Egypt warned of "grave consequences" from an escalation in tensions between Israel and the Palestinians, in a statement from the foreign ministry carried by the state news agency.

It called for "exercising maximum restraint and avoiding exposing civilians to further danger".

French President Emmanuel Macron

French President Emmanuel Macron said on Saturday that he strongly condemned the attacks against Israel.

"I express my full solidarity with the victims, and their families and those close to them," Mr Macron wrote on X.

German Chancellor Olaf Scholz

"Terrifying news reaches us today from #Israel. We are deeply shocked by the rocket fire from Gaza and the escalating violence. Germany condemns these attacks by Hamas and stands by Israel," Mr Scholz said on social media.

British Foreign Minister James Cleverly

"The UK unequivocally condemns the horrific attacks by Hamas on Israeli civilians. The UK will always support Israel’s right to defend itself," Foreign Minister James Cleverly said in a social media post.

Ursula Von Der Leyen, President of the European Commission

"I unequivocally condemn the attack carried out by Hamas terrorists against Israel. It is terrorism in its most despicable form. Israel has the right to defend itself against such heinous attacks," Ms Von Der Leyen posted on X.

European Union Foreign Policy Chief Josep Borrell

"We follow with anguish the news coming from #Israel. We unequivocally condemn the attacks by Hamas. This horrific violence must stop immediately. Terrorism and violence solve nothing," Mr Borrell posted on X.

Turkish President Tayyip Erdogan

"We call for restraint from all parties," Erdogan said at a congress for his ruling AK Party in Ankara. "They must refrain from aggressive acts," he said.

Dutch Prime Minister Mark Rutte

"Just spoke with Prime Minister @netanyahu about the unprecedented attack by Hamas on Israel. I told him that the Netherlands unequivocally condemns this terrorist violence and fully supports Israel’s right to defend itself," Mr Rutte said on social media.

Russian Deputy Foreign Minister Mikhail Bogdanov

Russia is in contact with Israel, the Palestinians and Arab countries in connection with the escalation of the Israeli-Palestinian conflict, the Interfax news agency reported, citing Deputy Foreign Minister Mikhail Bogdanov.

"It goes without saying that we always call for restraint," he said.

Hezbollah

The Iran-backed Lebanese group Hezbollah, an arch foe of Israel, issued a statement on Saturday saying it was closely following the situation in Gaza and was in "direct contact with the leadership of the Palestinian resistance".

Following events involving Gaza militants who fired a barrage of rockets into Israel, the statement added that it was a "decisive response to Israel's continued occupation and a message to those seeking normalisation with Israel".

Palestinians inspect an ambulance hit by an Israeli strike.(Reuters: Ibraheem Abu Mustafa)

Ukrainian Foreign Ministry

"Ukraine strongly condemns the ongoing terrorist attacks against Israel, including rocket attacks against the civilian population in Jerusalem and Tel Aviv," the ministry said on X.

"We express our support for Israel in its right to defend itself and its people."

Italian Prime Minister's office

"The Italian government is closely following the brutal attack taking place in Israel. It condemns in the strongest terms the ongoing terror and violence against innocent civilians. Terror will never prevail. We support Israel's right to defend itself," it said in a statement.

Swiss Department of Foreign Affairs

"We call for an immediate end to the violence and for the protection of civilians," the department said on X.

Polish Foreign Minister Zbigniew Rau

"I strongly condemn Hamas' ongoing attacks on Israel. This baseless aggression and acts of violence, especially against civilians, are unacceptable. Our thoughts and prayers are with everyone affected by these terrible events," Mr Rau wrote on X.

Rockets are fired from Gaza toward Israel, following Israeli strikes in Gaza.(Reuters: Mohammed Salem)

Czech President Petr Pavel

"The attack conducted from the Gaza Strip is a deplorable act of terrorism against the State of Israel and the civilian population," Mr Pavel said in a statement.

"The rocket attacks and the infiltration of Hamas commandos into Israel will block any efforts for a peaceful solution to the Palestinian-Israeli conflict for a long time."

Israeli Prime Minister Benjamin Netanyahu postponed a trip to the Czech Republic, a long-time Israel ally, following the hostilities, a statement from the Czech presidential office said.

Belgian Foreign Affairs Minister Hadja Lahbib

"Belgium strongly condemns the massive rocket attacks against Israeli civilians. Violence and terror only perpetuates suffering and hinders the path to dialogue. Our thoughts are with all those affected. We are monitoring the situation closely," she said on X.

Greek Foreign Ministry

"Greece strongly condemns today's launch of heavy rocket attacks from Gaza against Israel. Greece stands with Israel and is deeply concerned by this unacceptable escalation of violence," the ministry posted on X.

Reuters