US President Donald Trump said on Thursday that he would not allow Israel to annex the West Bank, rejecting calls from some far-right politicians in Israel who want to extend sovereignty over the area and snuff out hopes for a Palestinian state.

"I will not allow Israel to annex the West Bank," Trump told reporters in the Oval Office. "No, I will not allow it. It's not going to happen."

Trump's response came after he was asked whether he had promised Arab leaders during a meeting at the United Nations this week that he would prevent any annexation.

Israeli Prime Minister Benjamin Netanyahu has vowed not to allow a Palestinian state and far-right members of his cabinet have threatened to annex the West Bank in response to the recent recognition of a Palestinian state by several Western countries.

Asked whether he had warned Netanyahu against such a move when they spoke earlier on Thursday, he said: "Yeah, but I'm not going to allow it.

"Whether I spoke to him or not – I did, but I'm not allowing Israel to annex the West Bank. There's been enough. It's time to stop now."

Trump also expressed optimism about a Gaza deal amid a growing push to end the war and free hostages held by Palestinian militant group Hamas since their October 7, 2023 attack on Israel.

"We spoke with Bibi Netanyahu today, and we spoke to all the leaders in the Middle East who are great people, and we're getting pretty close to having a deal on Gaza and maybe even peace," Trump said.

Netanyahu is due to visit the White House on Monday, Israeli officials say. (Agencies)