Days before Israel’s president, Shimon Peres, was to meet with President Obama, Mr. Peres said on Thursday that the United States must make clear to Iran that “all options are on the table,” but he acknowledged that there was disagreement over where to draw the “red line” that would set off military intervention.

President Shimon Peres says the White House must be resolute or Israel may have to go it alone.

“We need a total and clear commitment that the catastrophe of Iran will not create an impossible situation,” Mr. Peres said in an hourlong interview at a Manhattan hotel. “If you can achieve it by economic and political measures, yes, that’s the best way to start. But in order that the Iranians will take it seriously, you have to say, ‘Gentlemen, we’ll try the way which may be the best, but all the other options are on the table.’

“You have to be decisive,” he said. “You have to make a choice.”

Mr. Peres — who at 88 has held virtually every post in Israeli government and in defining his current role said, “The prime minister is to rule, the president is to charm” — is scheduled to see Mr. Obama on Sunday. The prime minister, Benjamin Netanyahu, meets Mr. Obama on Monday.

Though the Israeli newspaper Ha’aretz reported last week that Mr. Peres planned to tell Mr. Obama he did not believe Israel should make a unilateral strike against Iran, on Thursday Mr. Peres suggested that if the White House was not resolute, Israel might have to go it alone.

“This is an unavoidable situation,” he said. “It’s not exactly the Nazi situation, but my God, what a catastrophe.”

In a wide-ranging conversation that touched on the Palestinian conflict, the Arab Spring, Israeli cultural identity, racial discrimination, economic globalization and the Ten Commandments, Mr. Peres repeatedly invoked the importance of technology and a young generation, declaring at one point that “all ideologies are practically dead.” Despite the radical transformations in the politics of the countries surrounding his, Mr. Peres, who shared the 1994 Nobel Peace Prize for his role in the Oslo Accords, said that he still believed in discreet diplomacy as a path to peace, and that he continued to have meetings on all sides about the prospects for a two-state solution.

“I can say jokingly that peace and love are alike: you cannot achieve either of them unless you close your eyes,” he said. “Negotiation is not a matter of give and take. Every solution that exists is dead. If you have two solutions, don’t waste the time in trying to convince the other party about your solution. Try to create a third solution, which is unknown.”

Regarding Egypt, Mr. Peres said that the Muslim Brotherhood “won the Parliament; they didn’t win the situation,” adding that “the real problem of Egypt and the Middle East is poverty, not politics.” He avoided addressing the rise of political Islamists around the region in the wake of popular uprisings.

The interview took place in a suite at the Regency Hotel, surrounded by guards and behind a bulletproof pane they had placed in front of a window, a vase of flowers sandwiched between them on the sill. It came amid his new Facebook campaign, “Be My Friends for Peace,” yet the conversation was infused with his long perspective.

“When I remember those days, Israel was not a state, Israel was a doubt,” he recalled. “When I compare the present situation with the then-existing situation, then we were more desperate. My heart doesn’t fall easily. I am talking out of experience.”