Iranian Foreign Ministry spokesman Ramin Mehmanparast said Tuesday that Iran is "completely serious" about the upcoming nuclear talks with world powers in the Russian capital of Moscow.

Mehmanparast said in a weekly press briefing that the success of the talks depends on the positive approach and cooperation of the P5+1 -- China, France, Britain, Russia and the United States plus Germany.

Recognition of Iran's nuclear rights by the P5+1 would be instrumental for the success of the talks, he said.

Iranian Foreign Minister Ali-Akbar Salehi has expressed hope that the upcoming nuclear talks in Moscow would be a "step forward " in resolving the existing differences between Iran and the West, the semi-official Fars news agency reported Monday.

The next round of talks between Iran and the P5+1 is scheduled in Moscow on June 18 and 19.