MOSCOW, May 20 (RIA Novosti) - Russia is satisfied with the results of the first round of discussions with the United States on a new strategic arms reduction treaty, a diplomatic source close to the talks said on Wednesday.

A team of U.S. negotiators led by Assistant Secretary of State Rose Gottemoeller came to Moscow for the two days of official bilateral talks on a replacement for the Strategic Arms Reduction Treaty (START 1), which is set to expire on December 5, 2009.

"The talks were held in a constructive atmosphere and we consider them a success," the Russian source said.

"We have agreed to report the first results of the work on a new treaty at a Russian-U.S. summit in Moscow in early July," he added.

The sides also agreed to meet for the second round of talks in Geneva on June 1-3, the diplomat said.

Signed in 1991, START 1 obliges Russia and the United States to reduce nuclear warheads to 6,000 and their delivery vehicles to 1,600 each.

In 2002, a follow-up agreement on strategic offensive arms reduction was concluded in Moscow. The deal, known as the Moscow Treaty, envisioned cuts to 1,700-2,200 warheads by December 2012.

According to a report published by the U.S. State Department in April, as of January 1 Russia had 3,909 nuclear warheads and 814 delivery vehicles, including ground-based intercontinental ballistic missiles (ICBM), submarine launched ballistic missiles (SLBM) and strategic bombers.

The same report stated the United States had 5,576 warheads and 1,198 delivery vehicles.

Moscow, which proposed a new arms reduction agreement with Washington in 2005, expects the United States to agree on a deal that would restrict not only the numbers of nuclear warheads but also place limits on all existing kinds of delivery vehicles.

"The final result of the talks should certainly be a step forward compared to the current regime of limitations," Russian Foreign Minister Sergei Lavrov said on Wednesday.