Leaders of the United States, Canada, France, Germany, Italy and Britain on Sunday underscored their support for Israel and its right to defend itself, but also urged it to adhere to international humanitarian law and protect civilians.

In a joint statement issued after a virtual meeting on the ongoing war between Israel and the Hamas militant group, the leaders welcomed the release of two hostages by Hamas, and called for the immediate release of all remaining hostages.

U.S. President Joe Biden convened a meeting of the so-called Quint - the U.S., France, Britain, Germany and Italy - plus Canada after speaking with Prime Minister Benjamin Netanyahu of Israel.

The calls came amid growing fears that the Israel-Hamas war could mushroom into a wider Middle East conflict as Israel pounded Gaza and clashes on its border with Lebanon intensified.

In the statement, Biden, Canadian Prime Minister Justin Trudeau of Canada, French President Emmanuel Macron, German Chancellor Olaf Scholz, Italian Prime Minister Giorgia Meloni and British Prime Minister Rishi Sunak pledged to work together closely to support their citizens in the region, and especially those wishing to leave Gaza.

They welcomed the arrival of the first aid convoys in Gaza, and pledged to continue working with regional partners to ensure "sustained and safe access" for the 2.2 million people in Gaza to food, water, medical care and other humanitarian assistance.

They also agreed to continue close diplomatic coordination, including with key partners in the region, to "prevent the conflict from spreading, preserve stability in the Middle East, and work toward a political solution and durable peace."

Biden and Netanyahu discussed the arrival of the first aid convoys to Gaza and "affirmed that there will now be continued flow of this critical assistance," the White House said.

The two men also discussed efforts to free more of the more than 200 hostages taken by Hamas, including some U.S. citizens.

"Biden spoke separately with Pope Francis and they discussed the need to prevent escalation in the region and to work toward a durable peace in the Middle East," the White House said.

The Vatican earlier said the call, which lasted about 20 minutes, "focused on conflict situations in the world and the need to identify paths to peace."