By Adrian Croft and Steve Gutterman
LONDON/MOSCOW (Reuters) - Russia's military chief of staff said on Thursday that Moscow could carry out pre-emptive strikes on future NATO missile defense installations in Europe to protect its security - a stark warning against a system the Kremlin sees as a threat.
General Nikolai Makarov's remark underlined Russian opposition to an anti-missile shield the United States and NATO are developing, an issue that will continue to strain relations after Vladimir Putin starts a six-year presidential term on Monday.
Makarov spoke at a conference where testy exchanges between the Russian hosts and U.S. and NATO officials pointed up the distance the old Cold War foes still have to go for a deal to cooperate on missile defense, an arrangement both say they want.
Washington says the missile defense system, due to be completed in four phases by about 2020 and including interceptor missiles based in Poland and Romania, is meant to counter a potential threat from Iran and presents no risk to Russia.
But a mistrustful Moscow says the West will gain the ability to shoot down Russian intercontinental ballistic missiles (ICBMs) in a few years, weakening Russia's nuclear deterrent.
Makarov repeated Kremlin threats to deploy more missiles in southern and northwestern Russia for potential strikes against the installations and said Moscow could act pre-emptively if it saw the need.
"Decisions on the pre-emptive use of ... attack components will be taken in the period of heightening tension," he told the conference of government officials and experts.
He said deploying such weapons, let alone using them to attack the missile shield, would be an "extreme measure" Russia hoped never to resort to, and later suggested that would be an option only if an imminent, severe security threat were spotted.
But Makarov said European states should decide whether protection against a possible future threat from nations such as Iran was worth the risk of facing Russian weapons that would pose a "real threat" to countries hosting the facilities.
Makarov said the Western system would have the potential to intercept Russian strategic ballistic missiles by 2017-18.
He spoke ahead of a NATO summit in Chicago on May 20-21 at which the shield's first phase is to be declared up and running.
HOPE FOR AGREEMENT, BUT NOT SOON
Despite Russian opposition to the shield, NATO Secretary-General Anders Fogh Rasmussen said the alliance is hopeful of reaching a deal with Moscow on missile defense.
He said it would not happen by the time of the summit - a target some Western officials had voiced earlier.
"We will continue our dialogue with Russia ... after the Chicago meeting," Rasmussen told reporters after talks in London with British Prime Minister David Cameron.
Russia and NATO agreed in 2010 to seek ways to cooperate on missile defense but have failed to reach a deal.
The Kremlin wants a legally binding guarantee the system will not be used against Russia. The United States says it cannot agree to any formal limits on missile defense.
Asked whether an agreement could be reached with Moscow, Rasmussen said, "I'm hopeful that we can."
The conference in Moscow drove home the divide, however.
Participants were shown computer-generated images that Russian generals said depicted the reach of radars and interceptor missiles to be deployed as part of the shield.
Dome-like designs displaying interceptor ranges and blips of light representing Russian missiles headed for U.S. cities lit up the screen.
A deputy to Makarov, General Valery Gerasimov, said the computer modeling showed that the interceptors would, in several years, be capable of hitting Russian missiles.
U.S. and NATO officials disagreed with the hi-tech presentation and said the anti-missile system would not undermine Russia's security.
"I must say that I am not convinced," said NATO Deputy Secretary-General Alexander Vershbow, a former U.S. ambassador to Russia. He said the NATO interceptors would be "simply in the wrong place" geographically to counter Russian missiles.
Madelyn Creedon, U.S. assistant secretary of defense for global strategic affairs, said the shield could not intercept Russian missiles targeting the United States. "The Russian strategic deterrent is now, and will remain, secure," she said.
Ellen Tauscher, U.S. special envoy for strategic stability and missile defense, said no deal was likely this year because of the U.S. presidential campaign and the settling-in period the new Russian administration will need after Putin's inauguration.
"It's going to be a deal at the presidential level, so I think it's going to be sometime hopefully next year," she told reporters at the conference. "But in the meantime, we've got a lot of work to do to dispel the mistrust."
(Editing by Mark Heinrich)