Israel officials on Wednesday cautiously welcomed resumed nuclear talks between the major powers and Iran.

“I’m very happy that they are opening discussions,” said Netanyahu’s national security adviser, Yaakov Amidror.

“There will be no one happier than us, and the prime minister said this in his own voice, if it emerges that in these talks Iran will give up on its military nuclear capability,” he told Israel Radio.

EU foreign policy chief Catherine Ashton on Tuesday formally accepted Iran’s offer of talks with the United States, Russia, China, France, Britain and Germany saying Iran should have to show “real progress.”

Ashton said the powers sought assurances on “the exclusively peaceful nature of Iran’s nuclear program, while respecting Iran’s right to the peaceful use of nuclear energy.”

Ahead of his White House meeting with US President Barack Obama on Monday, Netanyahu demanded Iran’s enrichment stop and its uranium with a higher than the 3.5 percent purity necessary for electricity generation.

Iran has been enriching its stockpile to 20% purity, which is considered a jumping off point should Iran decide to make a sprint for 93% enriched “weapons grade” uranium.

Tehran insists it is enriching to 20% for medical research purposes, but proliferation experts say Iran does not have an advanced enough biomedical research sector to support such a claim, and is enriching far more uranium than is necessary for such experiments.

Past contacts with Tehran, who International Atomic Energy Agency officials charge with intentionally obstructing its nuclear inspectors, have collapsed due to disputes over the scale of Iran’s uranium enrichment program, and stockpiling of the fissile material.

Israel is widely believed to be considering a strike in Iran’s nuclear facilities to disrupt what Jerusalem sees as a bid for an atomic bomb by a state that has repeatedly called for the Jewish state’s destruction.

Netanyahu has said Tehran must dismantle its heavily fortified enrichment facility near Homs, fully account for its uranium stockpiles, and allow international inspectors full access to its nuclear facilities to avoid military strikes.

But despite Iran’s claim it is now ready to talk, Israeli officials remain skeptical

“It should be clear that without a real military alternative, the Iranians will not relent in the negotiations. And without there being a serious alternative, they will not enter the negotiations, and in any event there has to be readiness for the negotiations failing,” Amidror said.

Netanyahu’s spokesman Liran Dan told reporters there had been no US effort to veto or endorse any military action by Israel on Iran.

“A red light was not given. And if we’re already talking about colors, then a green light was not given either,” he said in remarks to both radio stations. “If there are red lines being discussed, they are not between us and the Americans, but rather, between the international community and Iran.”