MOSCOW (AFP) - Russia said on Thursday that it was relatively optimistic after holding bilateral talks with Iran ahead of next week's negotiations between world powers and Teheran over its nuclear programme.

Iran has been talking separately with most of the members of the P5+1 group - the five members of the United Nations Security Council plus Germany - before the next round of talks begin in Vienna on June 16.

"We can say that the working out of a deal... is progressing," Russian negotiator, Deputy Foreign Minister Sergei Ryabkov, was quoted as saying by Russian news agencies after talks in Rome on Wednesday, which followed discussions the Iranians held with the United States and France.

"After these talks we are relatively optimistic ahead of the new round of negotiations that will begin on Monday in Vienna," Mr Ryabkov said.

He underlined that the talks were aimed at sketching out potential areas of progress and problems for the Vienna negotiations, due to last from June 16 to 20.

"As far as we can tell, the Iranian delegation has done important work with our American and French colleagues over the past two days," Mr Ryabkov said.

"We are going from a simple discussion to the search for concrete solutions," he said, adding that the possibilities of progress were appearing for "certain aspects" of the tortuous negotiations.

The P5+1 group and Iran secured an interim deal on Teheran's controversial nuclear programme in November after marathon talks in Geneva.

The deadline for a final accord was set as July 20, but several players including Iran have already said a six-month extension may be needed.

Ahead of next week's round of negotiations, Iran is holding bilateral meetings with all members of the P5+1 group except for China and Britain.

Washington and the other P5+1 states are seeking solid commitments that will ensure Iran's stated desire for a peaceful atomic energy programme is not a covert attempt to build a nuclear bomb.

For Iran, the goal is to make a leap towards ending the international sanctions, notably those imposed by the United States, that have battered its economy.

The P5+1 comprises Britain, China, France, Russia, the United States and Germany.