Washington, keen to allay Moscow's fears over its planned missile defence system, has invited Russians to visit its Missile Defense Agency (MDA) and participate in tests, a newspaper said on Thursday.

Citing sources, the Kommersant broadsheet said Russia was sceptical about the possible results of US proposal and was in no hurry to accept the offer.

Despite attempts to "reset" US-Russia relationship, Moscow and Washington have so far failed to reach a breakthrough on a missile shield project for Europe, with the Kremlin complaining that the US system would weaken its defenses.

"The United States has invited Russian technical specialists to visit a Missile Defense Agency base in Colorado Springs with their own equipment and to see for themselves that the US missile shield does not pose a threat to Russia," the newspaper quoted a diplomatic source in one of the NATO member countries as saying.

"There has not been a reply from Russia so far however."

The agency's Integration and Operations Center is located in Colorado Springs, Colorado.

Citing sources, Kommersant said Washington had invited a delegation of Russian defense officials led by Deputy Defense Minister Anatoly Antonov to visit the Colorado Springs-based command.

Russian Deputy Foreign Minister Sergei Ryabkov confirmed to Kommersant that his country had received the offer but declined to offer details.

More importantly, said the newspaper, Washington invited Russians for the first time to participate in missile tests scheduled to take place in the Pacific next spring, with the invitation being signed by MDA head Patrick O'Reilly.

The Russians however have showed little enthusiasm because they remain sceptical about Washington's intentions and a US refusal to provide written guarantees that the missile system would not target Moscow.

"We don't very much trust the results of these tests," a source close to the Russian defense ministry told Kommersant, adding there was no guarantee that the parameters they were shown would not be changed in the future.

The Russians have also complained that they will not be able to take their own monitoring equipment to the missile tests next year, the newspaper said.

"We have been offered to take our binoculars there and trust the readings of the US devices," Kommersant quoted a Russian diplomat as saying.