A regular round of negotiations with the group was held Monday in Geneva.

The next round of negotiations will be focused on "talks for cooperation" and "finding common grounds for cooperation," Iranian diplomatic sources said.

"The expectation is that the P5+1 will also help establish a constructive and positive atmosphere in this round of talks by modifying its previous approach," Iranian Foreign Ministry spokesman Ramin Mehmanparast was cited by the country's Press TV as saying.

The West, led by the United States, suspects Iran of pursuing a secret nuclear weapons program, but the Islamic Republic, under a few sets of international sanctions already, insists it needs nuclear power solely for civilian purposes.

Russia does not believe Iran plans to develop nuclear weapons but supports efforts by the International Atomic Energy Agency to clarify the situation, Prime Minister Vladimir Putin said earlier.

Asked during a satellite interview with U.S. talk show host Larry King aired on CNN last week of what Russia's attitude is toward Iran's nuclear program, Putin said: "Iran's nuclear program has been implemented for 20 years."

The Iran Six, which comprises Russia, the United States, China, Britain, France and Germany, has been trying since 2003 to convince Iran to halt its uranium enrichment program and to alleviate concerns about its nuclear ambitions.