With the negotiations set to resume in Vienna, top Israel diplomat Yair Lapid was scheduled to meet Monday with British Prime Minister Boris Johnson and Foreign Secretary Liz Truss in London, and with French President Emmanuel Macron in Paris on Tuesday.

The remaining partners to the deal -- Iran, China, Russia, Germany, France and Britain -- are due to meet directly, with a US delegation in the Austrian capital to participate indirectly.

Former Israeli prime minister Benjamin Netanyahu was among the most vocal critics of the 2015 deal, which was designed to prevent Iran from acquiring a nuclear arsenal by imposing strict limits on its nuclear programme in return for sanctions relief.

His successor Naftali Bennett has also voiced concern about a revival of the accord with Israel's arch foe.

"Israel is very concerned about the willingness to lift sanctions and allow the flow of billions to Iran, in exchange for insufficient restrictions on the nuclear programme," Bennett said ahead of a cabinet meeting Sunday.

"This is a message that we are conveying in every way, both to the Americans and to the other countries that are negotiating with Iran. The foreign minister will deliver the same message at his meetings in London and Paris this week," Bennett said.

But the Israeli premier has made clear he will not replicate Netanyahu's approach of publicly chastising key ally Washington as the negotiations play out.

Netanyahu's 2015 speech to a Republican-controlled Congress -- without an invitation from then president Barack Obama -- to blast the Iran negotiations hurt US-Israeli relations.

Netanyahu cheered when Obama's successor Donald Trump unilaterally withdrew from the accord in 2018.

A year later, Iran began retaliating by rolling back its nuclear-related commitments, such as breaching the limits laid down in the accord on its stockpile of enriched uranium.

Trump's successor Joe Biden has said he wants the US to return to the deal, but Washington has accused Iran of dragging its feet and making "radical" demands.