US Secretary of State Antony Blinken, in Israel to push for a Gaza truce, said on Monday ongoing negotiations were "maybe the last" chance to reach an agreement to end the war.

"This is a decisive moment -- probably the best, maybe the last, opportunity to get the hostages home, to get a ceasefire and to put everyone on a better path to enduring peace and security," Blinken said as he met Israeli President Isaac Herzog.

The top US diplomat said President Joe Biden had sent him "to get this agreement to the line and ultimately over the line".

"It is time for it to get done. It's also time to make sure that no one takes any steps that could derail this process," Blinken said.

"We're working to make sure that there is no escalation, that there are no provocations, that there are no actions that in any way could move us away from getting this deal over the line, or, for that matter, escalating the conflict to other places, and to greater intensity."

Blinken, on his ninth visit to the Middle East since Hamas's October 7 attack on Israel, is scheduled to meet later on Monday with Prime Minister Benjamin Netanyahu.

The visiting secretary of state said it was a "fraught moment" in Israel and warned against any moves that could heighten regional tensions, following threats from Iran and Lebanese armed group Hezbollah to avenge the recent killings of two militant leaders.

Herzog, who holds a largely ceremonial role, said Israelis wanted to see the return "as soon as possible" of hostages still held in Gaza since the October 7 attack that triggered the war.

"There is no greater humanitarian objective, and there's no greater humanitarian cause, than bringing back our hostages," Herzog told Blinken.