Sen. Howard W. Cannon (D-Nev.) warned the Intersate Commerce Committee yesterday not to take any major policy actions that would alter fundamental regulation of the trucking industry until Congress has a chance to act.

In a tough speech to members and staff of the ICC attending a federal-state workshop on regulation, the powerful chairman of the Senate Commerce Committee announced a timetable for congressional action on a motor carrier measure designed to get a bill on President Carter's desk by next June 1.

Cannon indicated he sympathizes with the ICC's desire to update a 44-year-old statute, but he argued that unilateral action to interpret the law in new ways could backfire.

"I know that it is totally unrealistic to assume that a 1935 congressional statement of policy can be applied to 1979 transportation problems,; Cannon said, but added, "I do not believe that the ICC should embark upon a course of action to redefine completely and unilaterally our national transportation policies.

"Major changes in the regulatory structure should be made by the Congress of the United States," Cannon told them. "The Congress may have ducked this responsibility in the past, but it will not do so this time."

Cannon's remarks reflected a growing unhappiness in Congress with what members perceive as wayward agenices; he specifically mentioned the Federal Trade Commission and referred to an action taken by the Civil Aeronautics Board which he said violated the intent of Congress.

Although the regulated trucking industry has opposed legislation, Cannon said he had consulted with its members and they are now anxious to remove the uncertainty that dominates trucking. "I think they're almost unified that we go ahead," he told reporters later.