TEHRAN, Iran — Iran and Western negotiators on Tuesday reported they were nearing an understanding on the details of implementing the landmark interim nuclear accord reached between Tehran and world powers in November.

The nuclear accord puts strong limits on Iran’s uranium enrichment program in return for an easing of some international sanctions on Tehran for six months while a permanent deal is negotiated. The United States and its allies believe Iran’s nuclear program is aimed at producing a nuclear weapon, a claim that Tehran denies, saying it is intended only for peaceful purposes.

The past month, experts from Iran and the so-called “P5+1″ countries — the US, Britain, France, Russia, China and Germany — have held several rounds of talks in Geneva to work out details on carrying out the agreement. The most recent session was on Monday.

A member of the Iranian negotiating team, Hamid Baidinejad, said the sides had had “achieved a mutual understanding” and that implementation of the accord would begin in January, according to the semi-official news agency ISNA.

State television also quoted senior Iranian nuclear negotiator Abbas Araghchi as saying he may meet again with Helga Schmid, a senior European Union negotiator, next week.

The Europeans said there had been progress, but some points still needed to be finalized, without elaborating.

Michael Mann, spokesman for EU High Representative Catherine Ashton, said the experts would now report back to their home governments and contacts would continue “to finalize a common understanding of implementation.”

He said in an email statement that the world powers are “fully committed to an early implementation” but did not elaborate on the timeframe.

A US State Department official said there has been progress in the talks and the teams have taken “a few outstanding points” back to their governments for consultation. “The two sides expect to finalize the implementation plan soon,” the official said.

The official spoke on condition of anonymity to discuss the closed-door talks.

Under the accord, Iran is to limit enrichment to producing uranium enriched at 5 percent, the level needed to power a reactor to produce electricity. Uranium enriched to around 90 percent is needed to produce a nuclear warhead. Iran would also neutralize its stockpile of 20-percent-enriched uranium, a level used to power research reactors.

Copyright 2013 The Associated Press.