News that international negotiators missed yet another deadline for an agreement limiting Iran's nuclear program is being welcomed by skeptics of the process, who say it's better than being stuck with a bad deal.

Representatives of Iran and the P5+1 countries — the United States, Britain, France, Germany, Russia and China — agreed Tuesday to extend talks on a final agreement to July 7.

This is the fourth time efforts to craft that deal have slipped past deadlines the negotiators themselves set, again leaving in place a November 2013 interim deal that was supposed to last only six months.

"It's a move that we've seen three times before ... it still requires more negotiating so it's the negotiations that keep on giving," said Michael Doran of the Hudson Institute, who was a National Security Council official under then-President George W. Bush.

What hasn't changed is the deadline on Capitol Hill. If Congress receives an agreement with Iran by July 9, it will have only 30 days to review it. If the deal comes in later, Congress has 60 days, giving opponents more time to argue against the deal.

As in the past, the delay has raised concerns that Iran is playing for time and has prompted calls for President Obama to walk away from the talks to increase the pressure. That position has been bolstered by the fact that the interim agreement seems to be holding at least well enough to provide cover for such a move.

"Rather than rush to meet politically-driven deadlines, the White House should work cooperatively with Congress to increase pressure for Iran to accept a stronger deal that requires it to confess all nuclear weapons activities, to dismantle its vast nuclear program, and to permit 'anywhere, anytime' international inspections at civil and military sites for decades," said Sen. Mark Kirk, R-Ill., co-author of a bipartisan bill to impose tougher new sanctions on Iran that the White House opposes.

Senate Foreign Relations Chairman Bob Corker, R-Tenn., has been arguing for months that the interim deal should be allowed to stand while the United States and its partners reassess whether Iran is serious about making the compromises necessary to ensure its nuclear program is not aimed at building weapons.

"I would urge you to please pause and consider rethinking the entire approach. Walking away from a bad deal at this point would take courage, but it would be the best thing for the United States, the region and the world," Corker wrote in a June 15 letter to Obama.

An apparent hardening of Iran's position has bolstered those arguing for a pause in the talks.

In a June 23 speech, Ayatollah Ali Khamenei, Iran's supreme leader, laid out several "major red lines" that appeared to be a backtracking of Iran's position from a framework announced April 2, including no international inspections of Iran's military sites and the "immediate removal of economic, financial and banking sanctions" on the signing of any nuclear agreement.

Neutral experts agree that the first condition would make any agreement unverifiable, and the second would become a serious issue for Congress if the administration agrees to that condition, since most U.S. sanctions in that area were imposed because of Iran's continuing support for terrorism, not the nuclear issue. Obama and Secretary of State John Kerry have repeatedly promised lawmakers they would lift only nuclear-related sanctions as part of any deal.

A day after Khamenei's speech, the Washington Institute for Near East Policy released an open letter signed by five former Obama administration advisers on Iran and a number of other former officials, including former CIA Director David Petraeus and retired Gen. James Cartwright, former vice chairman of the Joint Chiefs of Staff.

The letter took a pessimistic tone toward a deal taking shape and suggested that the United States should stay at the negotiating table until a "good" deal is reached, regardless of timing, while keeping the interim agreement in effect.

On Tuesday, Obama said if Iran can't abide by the terms in the April 2 framework "that's going to be a problem."

"If we can't provide assurances that the pathways for Iran attaining a nuclear weapon are closed and if we can't verify that — the inspections regime — the verification regime is inadequate — then we're not going to get a deal, and we've been very clear to the Iranian government about that," he continued.

Doran suggested, however, that Obama would try to accommodate the Iranians if necessary to keep the talks going.

"My inclination is to say that they are inclined to make major concessions," he said. "The Iranians have played us on every other deadline and they are doing so again."

Susan Crabtree contributed to this report.