Russia's foreign spy chief said military forces from other countries deployed at bases along Russia's periphery are a threat to the nation, a Russian news agency reported Monday.

In comments that appeared directed at U.S. forces deployed on bases in former Soviet countries, the Interfax news agency quoted Sergei Lebedev, head of the Foreign Intelligence Service, as saying that Russia no longer had a "main adversary" as during the Cold War.

But "Russians cannot help but be concerned about new military bases and military contingents being deployed around our country," he was quoted as saying.

Russia has watched warily as the United States deployed forces to the Central Asian countries of Kyrgyzstan and Uzbekistan and strengthened military and political ties with Ukraine and Georgia. Also, the three Baltic nations of Latvia, Estonia and Lithuania joined NATO in 2004 over Moscow's strong objections.

Earlier this year, Uzbekistan evicted U.S. forces from a base there after Washington criticized Uzbekistan's authoritarian regime for a violent crackdown on a demonstration in May and other human rights abuses.

Kremlin leaders have also been jittery about mass protests that brought the opposition to power in Georgia, Ukraine and Kyrgyzstan over the past two years — protests that Russia says were backed by the West.

Lebedev did not name any specific countries that Russia considered a threat.

"New, but no less serious threats and challenges facing our state's security have replaced old threats and challenges," he was quoted as saying. "Today the most serious threats are from international terrorism, from religious and nationalist extremism."

Lebedev also said that the Foreign Intelligence Service had no information that Iran was building nuclear weapons and he saw no reason to attack Iran.

Russia is helping Iran build a nuclear reactor at Bushehr, a project that Tehran says is intended strictly for electricity generation. The United States, however, accuses Tehran of using the project as part of an effort to build atomic weapons.

Israeli officials and politicians have openly discussed the possibility of an attack on Iran, either alone or with other countries, aimed at crippling its nuclear development capabilities.

"We have been monitoring the events surrounding Iran carefully," he was quoted as saying. "As of now, we have no information that Iran is developing nuclear weapons.

"Consequently, there is no reason to use force against Iran," he said.

Separately, Lebedev was quoted as saying by Interfax that nearly three-quarters of Al Qaeda's leadership has been destroyed over the past four years. And he said Russia itself had succeeded in killing several Al Qaeda-linked militants who were operating in Russia's troubled Caucasus region, where Chechnya is located.

Last week, Russia authorities announced they had killed Saudi-born Abu Omar al-Seif, who analysts said was a conduit for foreign funding of terrorist activities. He apparently had taken over as Al Qaeda's representative in Chechnya after the April 2004 killing of another Saudi-born terror suspect, Abu Walid.