Geneva, Jan 19 (IANS): Nuclear negotiators of Iran and the P5 1 countries wrapped up their second round of talks concerning Tehran's nuclear energy programme in Switzerland.

Following five days of closed-door negotiations, which saw the two sides make intensive efforts to narrow down their differences and ink a comprehensive deal, the talks ended Sunday, Press TV reported.

Tehran and the P5 1 group - Russia, China, France, Britain, the US, plus Germany - agreed to resume their discussions next month.

The two sides are yet to decide the date and location of their next round of discussions.

The Iranian deputy foreign minister described the Geneva discussions as "good" and "extensive".

"We reviewed all subjects on the table and we had very serious and business-like negotiations," he added.

The minister, however, said Tehran and its negotiating partners are still working "to bridge the gap between the two sides".

The negotiators have stepped up their efforts to pave the way for a final, long-term accord aimed at putting an end to the 12-year-old dispute over Tehran's peaceful nuclear activities.

The latest round of talks were held included lengthy meetings between Iranian Foreign Minister Mohammad Javad Zarif and his US counterpart John Kerry in Geneva and Paris.

This was the second round of discussions since Tehran and the P5 1 group failed to work out a permanent nuclear deal by last November's deadline despite making some progress.

The two sides decided to extend their talks for seven more months until July 1.

Tehran and the six countries now seek to reach a high-level political agreement by March 1 and then confirm the full technical details of the agreement by July 1.

The scale of Iran's uranium enrichment and the timetable for the lifting of anti-Iran sanctions are being viewed as major points in the ongoing negotiations.