MOSCOW. April 3 (Interfax) - The organizers of the conference of the left-wing forces, which is scheduled to take place in Moscow on April 6, have certain doubts about the possibility of cooperation with the liberal opposition, but are hoping that the differences will eventually be resolved.

"Some left-wing opposition forces have great doubts about the expedience of working with the liberal opposition," Alexei Prigarin, first secretary of the Russian Communist Party, said at a pres conference given by the forum organizers in Moscow on Thursday.

At the same time, he believes the opposition forces have a "foundation" for cooperation.

In addition, Prigarin said the National Assembly, which will take place on May 17-18 and which will involve members of both left-wing and liberal opposition, will unite the entire non-parliamentary opposition, from ultra-right to ultra-left.

Sergei Udaltsov, leader of the Vanguard of Red Youth, also said there are problems in the issue of the union between the left-wing and right-wing non-parliamentary opposition.

At the same time, he pointed out that the conference participants have an optimistic attitude. "For this reason, there will be a result, even though it is unpredictable, and the Assembly will live," he said.

The organizers of the left-wing conference said one of the main purposes of the forum is to unite the left-wing opposition, but said such a union can hardly be expected to occur at the conference.

"We propose to create an organizational committee to prepare for the formation of this union, but it will not be formed on April 6," Udaltsov said.