Last week, Russian Defense Minister Sergei Ivanov ruled out any prospect of NATO using ex-Soviet Central Asian states for retaliatory attacks and Kvashnin himself strongly implied that Russian participation in any attack was unlikely.
Wednesday's remarks appeared to leave little room for doubt.
"We are not participating in the military action and have no plans to do so," Kvashnin told reporters after a meeting with Tajik President Imomali Rakhmonov.
He said their talks had focused on the situation in the region after the United States threatened to get Saudi-born Islamic militant Osama bin Laden "dead or alive."
Washington has called bin Laden the prime suspect in the attacks on New York and Washington which left thousands of people dead or missing, and thinks he is hiding in Afghanistan under the protection of the ruling Taliban.
Kvashnin said during his visit that he would also check on the state of Moscow's Tajik-based 201st mechanized division, the most redoubtable force in the region.
He said Tajikistan, whose fragile political stability depends to a large degree on Russia's military presence, had nothing to fear at the moment from the Taliban.
"It is not the time (for them) to make threats against Tajikistan," Kvashnin said, adding that Dushanbe could always count on Moscow's help in case of aggression.
Interfax news agency cited military sources in Tajikistan as saying Kvashnin's visit could be linked to alleged U.S. plans to launch operations against the Taliban from Afghan territories under the control of the Northern Alliance.
The Northern Alliance controls a strategic strip of land in northern Afghanistan bordering Tajikistan. Russian troops guard the border between the two countries.
The United States has launched a diplomatic offensive to recruit as much international support as possible for its "war against terrorism." Moscow has backed the call but cautioned against hasty and indiscriminate use of force.
Russian President Vladimir Putin has dispatched his Security Council secretary, Vladimir Rushailo, on a tour of the region and he was in Uzbekistan Wednesday.
The prospect of a U.S. attack on Afghanistan also brings an ominous message from veterans of Russia's decade-long war with Afghan guerrillas: You'll never win.
"You can occupy it, you can put troops there and keep bombing, but you cannot win," said Lt. Gen. Ruslan Aushev, who was decorated for bravery during the 1979-89 war.
"No matter how they prepare for a ground operation, it is hopeless," said Yevgeny Zelenov, a member of the Russian parliament and a veteran of the war.
The Soviet Union's brutal conflict in the mountainous land helped bring about the superpower's collapse. The Soviet Union said it lost 15,000 troops in Aghanistan, and unofficial estimates are much higher.
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