Israel announced Sunday that it was suspending the entry of supplies into Gaza, and threatened "consequences" for Hamas if it did not accept a proposal for a temporary extension of the truce in the Palestinian territory.

"Prime Minister Benjamin Netanyahu decided that, from this morning, all entry of goods and supplies into the Gaza Strip will be suspended," his office said in a statement.

"Israel will not accept a ceasefire without the release of our hostages. If Hamas persists with its refusal, there will be other consequences," the statement added.

Hamas slammed the move, calling it a "war crime" and saying it violated the terms of the ceasefire agreement between the two sides, the first 42-day phase of which just drew to a close.

A proposed extension of the first phase, which according to Netanyahu's office was put forward by US President Donald Trump's Middle East envoy Steve Witkoff, would last through Ramadan and end at Passover in mid-April.

According to the Israeli statement, the extension would see half of the hostages still in Gaza freed on the day the deal came into effect, with the rest to be released at the end if an agreement was reached on a permanent ceasefire.

Hamas said in a statement on Sunday that Netanyahu's "decision to suspend humanitarian aid is cheap blackmail, a war crime and a blatant coup against the (ceasefire) agreement".

The Palestinian group has consistently favored a transition to the second phase of the ceasefire, which would see the release of all remaining hostages and a more permanent end to the fighting in the war-ravaged Gaza Strip.

Following the announcement from Netanyahu's office, his spokesman Omer Dostri wrote on X: "No trucks entered Gaza this morning, nor will they at this stage."

Far-right Israeli Finance Minister Bezalel Smotrich, whose party is crucial to keeping Netanyahu's government in power, welcomed the decision to suspend aid.

Stopping aid "until Hamas is destroyed or completely surrenders and all our hostages are freed is an important step in the right direction", he said on Telegram, calling for a renewed fight "until total victory" against Hamas.

"We have remained in government to ensure this," he added.

Hamas called on "mediators and the international community to pressure" Israel to "put an end to these punitive, immoral measures against more than two million people in the Gaza Strip."

More than 15 months of war created a humanitarian crisis in Gaza, with the UN repeatedly warning the territory was on the brink of famine before the ceasefire allowed a surge of aid to enter.