US National Security Adviser Susan Rice assured Israel at high-level talks on Thursday that Washington remained determined to stop Iran developing nuclear arms, the White House said.

"The US delegation reaffirmed our commitment to prevent Iran from acquiring a nuclear weapon," said a White House statement released after talks in Jerusalem between Rice, Prime Minister Benjamin Netanyahu and senior officials from both sides.

"The delegations held thorough consultations on all aspects of the challenge posed by Iran, and pledged to continue the unprecedented coordination between the United States and Israel," it added.

Earlier, Netanyahu said the best defence against a nuclear Iran was to block it from developing such a weapon in the first place and he referred to a new round of talks between Tehran and world powers due to open next week in Vienna.

"The most important thing is that Iran does not attain the ability to develop a nuclear weapon, and that needs to be and must be the ultimate and most important goal of the current negotiations with Iran," he said.

"That needs to be the object of the talks, that is Israel's position, that needs to be the position of everyone who really wants to prevent the renewed threat of mass destruction by a radical regime," Netanyahu said at a ceremony marking the 69th anniversary of the allied defeat of Nazi Germany.

The White House statement said the Israeli-US talks Thursday also dealt with "other critical regional and bilateral issues," without elaborating.

"The delegations shared views candidly and intensively, in the spirit of the extraordinary and unprecedented security cooperation between our two countries," it said.

It was Rice's first trip to Israel since she took office last July and it came shortly after the collapse of US-brokered Middle East peace talks.

The White House is assessing whether to try to salvage its Middle East peace efforts after the collapse in late April of nine months of US-brokered negotiations vigorously promoted by Secretary of State John Kerry.

Netanyahu suspended negotiations after the Palestine Liberation Organisation, dominated by Abbas's Fatah movement, struck a reconciliation deal with Hamas militants, who control the Gaza Strip.

-- 'Catch 22' --

"Netanyahu is in a 'Catch 22' situation," senior Palestinian official, Nabil Shaath told a convention of the Israeli leftist party Meretz in Tel Aviv on Thursday evening.

"Before the reconciliation with Hamas, (the Israelis) argued that Fatah had no control over Hamas and therefore didn't represent all of the Palestinian people," he said.

"After the agreement with Hamas, they say we made a deal with a terror organisation."

Rice met for dinner late Thursday with Palestinian president Mahmud Abbas at his headquarters in the West Bank city of Ramallah and said that despite the halt in talks the US remained committed to the process.

"Ambassador Rice underscored that while we have come to a pause in the parties' talks, the United States believes the only way to achieve lasting peace is through direct negotiations that lead to two viable, independent states living side-by-side in peace and security," another White House statement said after their meeting.

Referring to the Hamas rapprochement: "She reiterated US policy that any Palestinian government must unambiguously and explicitly commit to nonviolence, recognition of the State of Israel, and acceptance of previous agreements and obligations between the parties," the statement said.

Abbas told his guest that the Palestinian people's interest, was "to seek the unity of land and people through the implementation of the reconciliation agreement and the formation of a government of independents to prepare free and fair elections," his spokesman Nabil Abu Rudeina said in a statement,