Russia's unexpected decision to send troops to Kosovo in advance of the arrival of NATO forces came after negotiations here broke down Friday about a planned Russian role in the peacekeeping operation.

The talks among Russia, Finland and the United States foundered on the issues of who would command a Russian peacekeeping force, where it would be located and how large it would be. Russia wants its troops to patrol their own sector in Kosovo and does not want them under NATO command; the western alliance rejects both those positions.

Early Friday, the unexpected movement of a convoy of several hundred Russian soldiers from Bosnia into Yugoslavia -- but not yet into Kosovo -- led Deputy Secretary of State Strobe Talbott to turn his plane around as he was heading to Brussels and return to Moscow for more discussions.

There was also a quickly arranged exchange of phone calls between Russian Foreign Minister Igor Ivanov and U.S. Secretary of State Madeleine K. Albright, who was in Macedonia. Ivanov assured Albright that the Russians were only taking up positions outside Kosovo's borders, in preparation to enter the province when there is an agreement. Ivanov made the same pledge in comments broadcast on Russian television.

Early this morning, however, news arrived from Kosovo's provincial capital of Pristina that Russian troops had arrived there and been welcomed by crowds of cheering Serbs.

The move appeared to be a deliberate display of Russia's impatience with the faltering negotiations over its peacekeeping role. The Russian troops entered Kosovo even as Talbott was in Moscow for the resumed talks to try to reach a settlement on Russia's role in the peacekeeping force.

There were signs of a possible disagreement between Russian civilian and military authorities.

On Friday, Ivanov had expressed irritation over a public threat by a senior Russian military officer, Gen. Leonid Ivashov, to make a deal with Belgrade unilaterally for a Russian-controlled peacekeeping sector in Kosovo.

Then, shortly after the Russian troops arrived in Pristina this morning, Ivanov told CNN it was unfortunate they had entered Kosovo and they had been ordered to withdraw immediately. The troops encamped near the Pristina airport and showed no sign of departing right away.

Gen. Ivashov, who headed the Russian delegation in military talks on the issue, had suggested that Moscow would try to claim a sector in northern Kosovo, an area populated by many Serbs, without reaching a deal with NATO. "We will not beg, `Give us this little piece,' " said Ivashov.

On Thursday, Talbott said the West could not accept a separate Russian command in the Kosovo peacekeeping force, known as KFOR. Russia has insisted that its troops will not operate under the command of NATO, which it harshly criticized for the airstrikes on Yugoslavia.

"The thing is that NATO had already pre-planned this operation, having divided Kosovo's entire territory into sectors, with NATO units, headed by NATO generals, participating in each sector. Russia is being offered only to participate in one of these sectors, naturally under NATO command," Ivashov added. He said President Boris Yeltsin believes "Russia must act independently, in close cooperation with but not subordination to NATO."