Leaders of a political group formed to challenge the Communist Party unveiled their platform Friday and said they planned to try to register with authorities but expected to be rebuffed.

At a crowded eighth-floor apartment in northwest Moscow, organizers of the Democratic Union gathered to discuss their plans for political action. At least a dozen uniformed policemen milled around the building entrance but made no attempt to stop those entering or leaving.The declaration of goals and principles followed a week of meetings in which the organizers said more than 150 Soviets from 27 cities took part in deciding political stands for the party formed on May 7.

Yuri Denisov, one of the party's 15 Central Coordinating Council members, said the Democratic Union would try to comply with laws requiring groups to register their activity.

"We will soon make an attempt to register our party," he told journalists. "But of course we expect problems with that, and we do not expect to succeed."

Council member Alexander Lukashev summed up the new group's goal as presenting an "opposition" to the Communist Party's monopoly on power and political thought.