Obama made the remarks in an interview with CNN’s Fareed Zakaria, which is set to air on Sunday.

He said that Iran’s “nuclear problem” should be resolved first and the accord reached between Tehran and the P5+1 group of countries on July 14 can provide grounds for reaching that goal “better than any alternative.”

Obama said, upon achieving that objective, it is possible to open more comprehensive talks with Iran on other issues, including the crisis in Syria. “But I don’t think it happens immediately,” he added.

When asked whether the military option was on the table if the agreement falls apart, Obama said, “I have a general policy on big issues like this not to anticipate failure.”

“And I’m not going to anticipate failure now because I think we have the better argument,” he emphasized.

Elsewhere in his remarks, the US president criticized Republicans, including Senate Majority Leader Mitch McConnell, who opposed the nuclear agreement.

“The reason that Mitch McConnell and the rest of the folks in his caucus who opposed this jumped out and opposed this before they even read it, before it was even posted, is reflective of an ideological commitment not to get a deal done,” Obama said.

Obama has launched an aggressive campaign of private entreaties and public advocacy to rally enough Democratic support to preserve the nuclear agreement ahead of a September vote on it in the Republican-led Congress.

Most Republicans oppose the nuclear agreement with Iran, but they need a two-thirds vote in both chambers of Congress to override a presidential veto, and to reach that threshold, Republicans need Democratic support.

Obama has accused the Israel lobby, AIPAC, of spending millions of dollars to spread false claims about the agreement, vowing to push back.

At a White House meeting this week, Obama told leaders of AIPAC that “he intended to hit back hard,” The New York Times reports, citing people present at the gathering.