The US urged Israel on Friday to ensure more humanitarian aid gets into Gaza and to do more to protect Palestinian civilians, as Israel’s Prime Minister said there would be no ceasefire in the nearly month-old war until Hamas releases hostages.

The leader of the Iran-backed Hezbollah militant group stoked fears that the conflict could widen by promising more attacks along the Lebanon border.

Israeli troops tightened their encirclement of Gaza City, the focus of their campaign to crush the enclave’s ruling Hamas militants, who launched a brutal attack on Israeli communities that started the war.

But ever since that October 7 assault, there have been concerns the conflict could ignite fighting on other fronts, and Israel and the Iranian-backed militant group Hezbollah have repeatedly traded fire along the Lebanon border.

In his first public speech since the war began, Hezbollah leader Hassan Nasrallah said his group had “entered the battle” with the past weeks’ unprecedented cross-border fighting.

“We will not be limited to this,” he said, suggesting escalation was possible. Still, Nasrallah stopped short of announcing that Hezbollah is fully engaging in the war.

US secretary of state Antony Blinken, on his third trip to Israel since the war began, reiterated US support for Israel in the war, saying it has the right to defend itself. But he said a “humanitarian pause” was needed to boost aid deliveries to Palestinian civilians amid growing alarm over the humanitarian crisis in Gaza.

After meeting Blinken, Israeli Prime Minister Benjamin Netanyahu said Israel “refuses a temporary ceasefire that doesn’t include a return of our hostages,” referring to some 240 people Hamas abducted during its attack. He said Israel was pressing ahead with its military offensive with “all of its power”.

Blinken said there had to be a substantial and immediate increase in humanitarian aid to Gaza, where “we need to do more to protect Palestinian civilians”. Without that, “there are no partners for peace”, he said, adding that it was critical to restore the path toward a two-state solution to the Israel-Palestinian conflict.

Hezbollah, an ally of Hamas, attacked Israeli military positions in northern Israel with drones, mortar fire and suicide drones on Thursday. The Israeli military said it retaliated with warplanes and helicopter gunships.