MOSCOW - The pause of talks between Iran and six major international mediators has sent a wrong signal, a senior Russian diplomat said Wednesday.

Five months after the Moscow round of nuclear talks between Iran and the UN Security Council's five permanent members, namely the United States, Britain, France, Russia and China, plus Germany, known as P5+1, the parties still have not reached an agreement on the place and date of next round of talks, Russian Deputy Foreign Minister Sergei Ryabkov said.

"This becomes unclear and sends a wrong signal," the diplomat told Itar-Tass news agency, adding the issue should be made clear soon.

As one of the mediators, Russia kept working on the schedule of the talks during its Christmas holidays and expected a clear result as soon as possible, Ryabkov said.

Iran and the P5+1 have held several rounds of talks over its controversial nuclear program, but no agreement has been reached so far. Both sides are currently in contact to prepare the grounds for another round of meeting.

According to the Russian diplomat, both the sextet and Iran agreed another round of talks would take place, though certain difficulties remained over coordination of the meeting's details.

Iran's chief nuclear negotiator Saeed Jalili said recently Tehran welcomes the readiness of the six major world powers to hold constructive talks with the Islamic republic.

Iranian officials have said that lifting sanctions is a primary step for the success of Iran's future nuclear talks with the P5+1. Iran has also reiterated that its right of nuclear enrichment for civilian ends should be recognized by the world powers.