OSLO, Norway - After tempestuous talks with their Russian counterpart on missile defenses, NATO foreign ministers on Friday turned to other issues that risk upsetting Moscow -- Kosovo, the further expansion of the Western alliance and a drive to build closer relations with Ukraine.

On Thursday, the NATO allies expressed concern over Russian President Vladimir Putin's declared intention to freeze compliance with a European arms control treaty.

"That message was met by concern, grave concern, disappointment and regret," NATO Secretary General Jaap de Hoop Scheffer told reporters after Russian Foreign Minister Sergey Lavrov confirmed Moscow's threat.

The Conventional Forces in Europe Treaty limits the number and locations of military aircraft, tanks and other non-nuclear heavy weapons around Europe. Withdrawal would allow Moscow to build up forces near its borders.

Putin's threat was just the latest indication of a growing divide between the former Cold War foes. The U.S. plan to extend an American missile shield to central Europe is just one source of annoyance. Western criticism of Russia's rights record, and Moscow's perception that the U.S. is dominating world affairs also have strained relations.

"Our partners are behaving incorrectly, to say the least," Putin said in his state-of-the-nation address on Thursday. "In case no progress is made during negotiations, I propose to discuss the possibility to end our obligations."

Secretary of State Condoleezza Rice fired back by insisting Moscow should live up to its obligations under the treaty. She called Russia's concerns "purely ludicrous" in a news conference at a meeting of NATO foreign ministers in Oslo, Norway.

Russian Foreign Minister Sergei Lavrov later added to the fire in a lengthy diatribe that recalled the language of the Cold War. He accused the U.S. and its NATO allies of upsetting the security balance in Europe, creating new dividing lines and treating Russia as an enemy.

"We cannot be unconcerned by the fact that NATO military infrastructure is creeping up to our borders," Lavrov said at a news conference after a NATO-Russia meeting in Oslo. "They are still looking for an enemy."

Like Putin, Lavrov spoke of suspending participation in the arms control treaty.

However, a Kremlin spokesman said later that Russia would not pull out if it could reach accommodation with the West. And Russian military experts suggested the threat was a symbolic raising of the ante in the missile shield showdown more than a sign of impeding military escalation. Russia has no actual interest in a buildup of forces because it faces no real military threat and has no plans to launch any attack, they said.

Lavrov was not attending the final day of the NATO talks where ministers from the 26 allied nations were due to discuss plans to further expand the Western alliance next year. Friday's discussions were expected to focus on the membership bids of Croatia, Macedonia and Albania.

Moscow has opposed successive enlargements of NATO into Eastern Europe. NATO's likely expansion into the Balkans does not please Russia, but the Kremlin has been much more concerned about the prospect that its neighbors Ukraine and Georgia also may be brought into the Western alliance.

Georgia's membership bid was not on the agenda Friday, but some NATO members are pushing for the alliance to open the door to the former Soviet republic.

Ukraine's pro-Russian Prime Minister Viktor Yanukovych has put the country's NATO membership on hold, but Foreign Minister Arseniy Yatsenyuk will join the NATO talks to discuss closer cooperation with the alliance. However, the talks are overshadowed by the political standoff in Ukraine between supporters of Yanukovych and pro-Western President Viktor Yushchenko.

On Kosovo, de Hoop Scheffer pressed Lavrov Thursday to support a U.N. plan that would grant independence to the Serbian province under international supervision. Lavrov gave no sign that Russia would relax its support for Serbia's opposition to the plan.

The Conventional Forces in Europe Treaty was signed in 1990 and amended in 1999 to reflect changes since the breakup of the Soviet Union, adding the requirement that Moscow withdraw troops from the former Soviet republics of Moldova and Georgia.

Russia has ratified the amended version, but the United States and other NATO members have refused to do so until Russia completely withdraws.

In his speech to parliament and government officials, Putin accused NATO members of taking advantage of the situation to build military bases near Russia's borders, and said the missile defense plans for the Czech Republic and Poland were undermining the balance of military power in Europe.

"It is high time that our partners proved their commitment to arms reductions not by words but by deeds," Putin said. "I consider it worthwhile to declare a moratorium until all NATO countries ratify (the treaty) ... and begin to strictly abide by it."

Rice repeated U.S. assertions that any defense system in Europe would be useless against Russia's enormous missile arsenal and urged Russia to accept U.S. offers to cooperate in combatting new threats, notably from Iran and North Korea. She insisted that Russia, Europe and the United States were all at risk from Iran developing long-range missiles.

She said the U.S. would continue efforts to "demystify" the plan for the Russians by pushing an offer to share data and technology with Moscow.