Talks over Iran's nuclear program will continue for another seven months after negotiators failed to reach an accord by a Monday deadline.

Citing "critical headway," diplomats set June 30, 2015 as the new target date to limit Iran's enrichment capabilities in exchange for eased sanctions, the Washington Post reported. According to the newspaper, "diplomats framed the extension as a chance to build on momentum achieved in the latest rounds and concentrate on working out specific ways to implement and enforce a deal to limit Iran's nuclear program," even though they did not adhere to the Monday deadline.

"Substantial progress was made," Russian Foreign Minister Sergei Lavrov told the Tass news agency.

Along with China, France, Germany, the United Kingdom and the United States, Russia is part of the so-called P5+1 group, which is negotiating the prospective agreement with Iran.

The parties "had set a deadline of midnight Monday to come to a final agreement on a mechanism whereby Iran's pathways to develop a nuclear weapon would be closed in return for relief from international sanctions," Fox News summarized.

"Instead, British Foreign Secretary Philip Hammond said it 'was not possible to meet the deadline' due to wide gaps on well-known points of contention, including levels of uranium enrichment and the number of centrifuges Iran would be allowed to operate," the site said..

The Israeli newspaper Haaretz noted that "the P5+1 and Iran will reconvene in December at a yet-to-be-determined location."

According to the Washington Post, a "headline agreement" is expected within three months.

Lavrov said that technical details would be worked out before the end of June.

Israeli Prime Minister Benjamin Netanyahu on Monday praised the decision to extend the talks, according to Haaretz.

"We have said consistently that no agreement was better than a bad agreement," Netanyahu said. "The agreement that Iran was aiming for was very bad indeed. It is extremely important that this agreement has been avoided.

Netanyahu has been pushing for a hard line on Tehran, whose nuclear program he contends poses a direct threat to Israel's security, as well as stability in the Middle East.

Given the extension,all sides have high stakes, but "diplomats involved in the talks have set clear markers ahead," according to the Washington Post.