The Washington public relations firm of Gray and Company announced yesterday that it will no longer represent the Marxist government of Angola, target of the latest U.S.-backed "freedom fighter" force under guerrilla leader Jonas Savimbi.

Saying the firm's representation had been "misinterpreted" in some quarters, a statement said Gray and Company's two months of service to Angola had aided "the flow of information and facts to assist both governments and those responsible for the U.S. foreign policy making process." The firm got $40,000 for the service.

A company spokesman said that, as recently as yesterday, the firm delivered to the State Department a message from Angola assuring U.S. officials that the Luanda government is prepared to cooperate in finding a solution to southern African tension.

The statement took issue with critics who charged that company Vice Chairman Daniel Murphy, a former national security assistant to Vice President Bush, had been working against U.S. policy interests by representing Angola's position.

The firm's statement said Murphy had "worked with determination to open the communications window. His actions only can benefit the established U.S. foreign policy objectives of a negotiated settlement in Angola."

A source familiar with the company acknowledged that political pressure, including demonstrations by young conservatives at the firm's Georgetown offices, was an element in the decision to drop the Angola account.