Iranian Foreign Minister Mohammad Javad Zarif and his Russian Counterpart Sergey Lavrov reviewed the latest developments in the process of the nuclear negotiations during a phone conversation on Monday

Iranian Foreign Minister Mohammad Javad Zarif and his Russian Counterpart Sergey Lavrov reviewed the latest developments in the process of the nuclear negotiations during a phone conversation on Monday.

The Iranian nuclear negotiators will leave Tehran for Lausanne, Switzerland, Wednesday for the next round of talks which is due to start either on Wednesday night or Thursday morning.

Zarif is to meet with his US counterpart John Kerry in Lausanne on Thursday.

The ninth round of talks between the Iranian and US nuclear negotiators was held in Lausanne on Friday afternoon in the presence of Zarif, Kerry, their deputies, Head of the Atomic Energy Organization of Iran (AEOI) Ali Akbar Salehi, US Energy Secretary Ernest Moniz, and EU foreign policy chief Federica Mogherini and her deputy Helga Schmid. The Iranian negotiators returned to Tehran on Saturday to participate in ceremonies celebrating the Iranian new year (which started on March 21).

Zarif said on Saturday that Tehran and the Group 5+1 (the US, Russia, China, Britain and France plus Germany) had found technical and political solutions to their differences. "Proper technical and political solutions have been found for the issues which couldn't be solved in the past," Zarif wrote on his facebook page.

"We have decided to return to Geneva on Wednesday to continue the talks, and God willingly, finalize the details of the solutions," Zarif said.

Earlier, Iranian Deputy Foreign Minister Sayyed Abbas Araqchi Araqchi said that the next round of nuclear negotiations with the world powers would start on Wednesday, March 25. The US and European countries require more consultations and arrangements with their governments to continue talks with Iran, he said.

Talks between Iran and G5+1 were very serious and extensive, he said, adding that nuclear teams at this juncture are in need of more negotiations and coordination, Araqchi added.

To the same reason, foreign ministers of the European states and the US will meet in Berlin on Saturday and the next round of talks with Iran will be resumed on March 25, he said.

Also on Tuesday, Salehi announced that Tehran and Washington had overcome their differences on technical issues with regard to Iran's nuclear program in most of the cases, adding that both sides were trying to resolve the remaining technical problems.

"We have agreed on 90 percent of technical issues," Salehi said after his second meeting with US Secretary of Energy Ernest Moniz in Lausanne, Switzerland, on Tuesday.