Russia wants more information on how it could participate in NATO's proposed joint missile shield ahead of a summit with leaders of the alliance, Russian Foreign Minister Sergei Lavrov said Monday.

"We would like to receive more information before the summit about how our NATO partners see Russia's participation in such a system," Lavrov said at a joint news conference with his German counterpart Guido Westerwelle.

The NATO-Russia summit will take place in Lisbon on November 20, directly after a NATO summit.

NATO will discuss setting up a joint alliance missile shield and has invited Russia to take part in it. Medvedev gave a cautious welcome to this idea, but said Moscow needed to hear more details.

"I hope that we manage to reach a common understanding prior to the summit in Lisbon about the existing risks and where concretely they come from" in order to determine the usefulness of the shield, Lavrov said.

The German foreign minister said he hoped that Russia would accept NATO's invitation to the missile shield in an interview on Echo of Moscow radio before he met Lavrov.

"Russia is unquestionably invited to participate, because we do not want to have different zones of security in Europe," Westerwelle said in comments translated into Russian.

"The summit in Lisbon is a window of opportunity to underline the strategic character of NATO-Russia relations and direct them to the future," Westerwelle said later at the news conference.

Moscow has fiercely opposed US plans to deploy an anti-missile system in eastern Europe.

Washington insists the missile shield is designed to fend off threats from rogue states like Iran and is not aimed at undermining Russia's missile force as a deterrent. It has now promised to modify its plans.