Communications Workers of American President Larry Cohen held a conference call with reporters Tuesday afternoon that was intended to attack Republicans for delaying White House nominations. But the union leader could not hold back his frustration with Senate Democrats for their lack of action on reforming the filibuster rule.

"To the Democrats: You had an opportunity. Why didn't you act? You must act," Cohen said, adding: "That is the question as much as the obstruction of the Republicans."

He then reiterated: "Democratic leadership: you need to act. These rules have not worked the entire time this president has been in office. What are you waiting for?"

The union leader also raged against the GOP, saying that "high-priced lawyers here in the US Chamber of Commerce" have gained control of the party and forced it to opposed collective bargaining rights.

"This is a conspiracy. That is the story that is not getting told," Cohen said adding: "They do it openly."

Cohen has been one of the most aggressive proponents of Senate Majority Leader Harry Reid, D-Nev., scrapping the Senate rule that requires the ascent of 60 senators before debate can continue on a bill.

Reid could scrap the rule with a simple majority vote and reportedly may have just barely enough votes to do it. He has thus far hesitated to act though, either for strategic reasons, fears that his coalition won't hold or that the precedent could haunt Democrats should they loose their majority.

In an interview last month with the Nation, Cohen said Reid will bear "lots" of responsibility if President Obama cannot get his nominations through the Senate.