Iran and US meet again to discuss nuclear agreement

US secretary of state John Kerry has met with Iran's foreign minister on the sidelines of a security conference in Germany, pressing Tehran to abide by its commitments over its nuclear programme.

Kerry's meeting with Javad Zarif on Sunday came after Iran agreed in November to halt its most sensitive uranium enrichment activities in return for an easing of western sanctions.

Implemented in January, the agreement will be in effect for six months while further negotiations are held aimed at reaching a permanent accord eliminating concerns that Tehran might build nuclear weapons. Iran denies such aims but says it is ready to reach a deal in exchange for full sanctions relief.

Catherine Ashton, the European Union's foreign policy chief, said after meeting with Zarif on Friday that Iran had agreed to a new round of negotiations in Vienna with the five permanent members of the UN security council plus Germany.

Kerry made clear that the US would continue to enforce remaining sanctions, according to a statement from the US state department. There was no immediate comment from Iran on the talks.

Under the six-month deal, Iran has agreed to halt its 20% enrichment programme, which produces uranium just steps away from military grade, but will continue enrichment up to 5%. It also will convert half of its stockpile of 20%-enriched uranium to oxide, and dilute the remaining half to 5%.

In return, the US and the EU simultaneously announced the lifting of sanctions on petrochemical products, insurance, gold and other precious metals, passenger plane parts and services. They also plan to release $4.2bn (£2.6bn) in Iranian assets of oil revenues blocked overseas, in eight installments over six months.

Kerry and Zarif have met several times since Iran's President Hassan Rouhani, a relative moderate, was elected last June, leading to a thaw in ties with the west after years of confrontation and hostile rhetoric.

The EU's foreign policy chief, Catherine Ashton, who co-ordinates the nuclear talks with Iran on behalf of the US, Russia, China, Britain, France and Germany, welcomed the meeting between Kerry and Zarif.

"It is incredibly important that as the international community now looks to build towards the comprehensive talks, that the dialogue is taking place and that we're working out how to develop a comprehensive approach to this," she told reporters in Munich.