Israeli Prime Minister Benjamin Netanyahu wears a face mask against COVID-19, bearing the US and Israeli flags, during a meeting with US special representative for Iran at the prime minister's office in Jerusalem on June 30, 2020. (ABIR SULTAN / POOL / AFP)

JERUSALEM - Israel held out the possibility on Tuesday it would not engage with US President Joe Biden on strategy regarding the Iranian nuclear program if he returns to a 2015 deal with Tehran.

The remarks by Israel’s envoy to Washington came at a touchy juncture for Prime Minister Benjamin Netanyahu. Up for re-election next month, he has revived tough rhetoric on Iran while not yet having any direct communication with Biden.

Israeli Prime Minister Benjamin Netanyahu's aides have privately questioned whether engaging with US counterparts might backfire, for Israel, by falsely signalling its consent for any new deal that it still opposes

The new administration has said it wants a US return to the 2015 nuclear deal - which former President Donald Trump quit, restoring sanctions on Tehran - if the Iranians recommit to their own obligations. Washington has also said it wants to confer with allies in the Middle East about such moves.

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“We will not be able to be part of such a process if the new administration returns to that deal,” Ambassador Gilad Erdan told Israel’s Army Radio.

Netanyahu aides have privately questioned whether engaging with US counterparts might backfire, for Israel, by falsely signalling its consent for any new deal that it still opposes.

Israel was not a party to the 2015 deal. It has powerful advocates within the US Congress, however, and Netanyahu’s threats to take unilateral military action on Iran if he deems diplomacy a dead end also figure into big-power planning.

“We think that if the United States returns to the same accord that it already withdrew from, all its leverage will be lost,” Erdan said.

“Essentially, the moment it removes the sanctions the Iranians will have no real incentive to negotiate and reach a deal that is truly capable of ruling out nuclear capabilities.”

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The Biden administration has said it wants to strengthen and lengthen constraints on Iran, which denies seeking nuclear arms.