A link to strengthen the recently frayed ties between organized labor and the Democratic Party will be completed tomorrow, when 20 labor leaders meet to discuss their roles as members of the party's new labor council.

Robert A. Neuman, communications director for the Democratic National Committee, says "calls are still going out" to those selected to serve on the panel. But labor sources say the council will include union leaders whose organizations have given substantial financial and political support to the party, as well as leaders from more conservative unions, such as those in the construction industry.

A DNC letter sent to prospective council members, and read to The Washington Post, said "participation in the labor council is limited to the presidents of each international union only." Union presidents unable to attend tomorrow's meeting will be allowed to send their next highest executive officer, the letter said.

Glenn E. Watts, president of the Communications Workers of America and a member of the council, said he believes the group "will be neither liberal nor conservative." He said he expects the group to help the labor movement "develop significant input into the policies of the Democratic Party."

Since the 1980 elections labor leaders, particularly those representing unions in the AFL-CIO, have said they would scrap their "neutral" political stance and establish a more visible presence within the ranks of the Democratic Party.

AFL-CIO President Lane Kirkland has argued that labor's lack of a political home in 1980 helped put Ronald Reagan in the White House and also contributed to the elections of other candidates who many labor leaders regard as anti-union.

The federation has since adopted a policy of endorsing and working for political candidates in primary elections, and has managed to place 15 representatives on the DNC and five on the party's executive committee.

Some of the federation leaders holding regular DNC positions also will double as labor council members. Watts, for example, serves on the DNC.

But not all federation members holding DNC positions are union presidents. And labor sources emphasized yesterday that the council is a separate group that will work closely with labor leaders in regular committee slots.

These developments do not set well with the Republican Party, which last month criticized Kirkland's political maneuvers in "Source," a magazine published by the Republican National Committee.

"Instead of participating through the democratic process, AFL-CIO leader Lane Kirkland has chosen a monogamous relationship with the Democratic Party while totally ignoring the party entrusted by the voters to run the government," the magazine said.