Russia has called on Tehran to fulfill its obligations in order to regain international trust in its nuclear program.

Deputy Foreign Minister Sergei Ryabkov told a media conference Tuesday Moscow was concerned over some aspects of Iran's nuclear program, but had no information to confirm military components in Iran's program.

Meanwhile, Ryabkov criticized the United States' stance on sanctions against Iran.

"The negotiations with Iran ... should address a mutually acceptable scheme that could help the parties strengthen confidence in each other (and) eliminate the sources of concerns over Iran's nuclear program," he said.

All the six international mediators had confirmed their readiness in Istanbul to remove the existing concerns over Iran's program, Ryabkov said, adding Moscow would also do its utmost to take a "creative approach" to the problem.

The latest Iran nuclear talks concluded in Istanbul Saturday, with both Iran and the six world powers describing them as positive and constructive.

The six, the United States, France, Russia, China, Britain and Germany, have spearheaded diplomatic efforts to persuade Iran to limit its nuclear program, which Iran says is purely peaceful but UN and Western leaders suspect has military purposes.