Jonathan S. Landay

WASHINGTON: President Barack Obama said Monday that the United States must test “in good faith” Iran’s readiness to negotiate a settlement to the feud over its nuclear program, even as Israeli Prime Minister Benjamin Netanyahu urged that tough sanctions — and the threat of military force — be maintained against Tehran and intensified if necessary.

After talks at the White House, Obama and Netanyahu both reiterated that Iran can’t be allowed to develop nuclear weapons, but the bulk of their comments illustrated the gap in how they view an unprecedented outreach to the West by Iran’s new government that was capped on Friday by a historic telephone call between Obama and the new Iranian president, Hassan Rouhani.

Speaking to reporters as he sat beside Netanyahu, Obama emphasized that Rouhani’s government must be given a chance to prove that it is prepared to hold serious talks on its nuclear program after years of stalemate. The Israeli leader — who has derided the Iranian diplomatic offensive as “sweet talk and a blitz of smiles” — conveyed a conviction of total mistrust.

“We have to test diplomacy,” Obama said. “We have to see if, in fact, they [Iran] are serious about their willingness to abide by international norms and international law, and international requirements and resolutions. And we in good faith will approach them, indicating that it is our preference to resolve these issues diplomatically.”

Obama stressed, however, that Iran will have to take concrete actions to assure the world that it is not developing nuclear weapons before it can receive relief from a raft of tough sanctions that are choking its economy.

“We enter into these negotiations very clear-eyed. They will not be easy,” he said.

Obama credited the sanctions with pushing Iran to seek a reopening of negotiations on its nuclear program with world powers, which stalled in April while Rouhani’s predecessor, Mahmoud Ahmadinejad, was still in power.

In contrast, Netanyahu said that sanctions and U.S. and Israeli threats to use military force must remain in place until the talks conclude successfully. That approach would rule out a phased removal of the measures that most experts consider the most promising avenue to an accord.

“I believe that it’s the combination of a credible military threat and the pressure of those sanctions that have brought Iran to the negotiating table,” Netanyahu said. “I also believe that for diplomacy to work, those pressures must be kept in place. And I think they should not be lessened until there is verifiable success.”

“In fact, it is Israel’s firm belief that if Iran continues to advance its nuclear program during negotiations, the sanctions should be strengthened.”

There currently is no proof that Iran is building a nuclear warhead.