The State Department said yesterday that it would have difficulty agreeing to a request from Marxist Angola for an emergency increase in famine-relief aid.

Department spokesman Charles E. Redman noted that total annual U.S. food aid to Angola averages $10 million to $11 million and that the U.S. government has been providing almost all the food aid distributed there by the United Nations children's fund, UNICEF.

At the same time, the U.S. government has been providing $15 million annually to the Union for the Total Independence of Angola (UNITA) rebels seeking to overthrow the Soviet- and Cuban-backed government.

Redman said Angola has made an emergency request to UNICEF for increased donations to combat widespread hunger. It is the Marxist government's largest request for international emergency aid.

"But our problem in making a decision is that it would appear that while oil revenues have gone up in Angola for the past year, that this money is not being spent by the Angolan government to address the urgent needs of this suffered population," he said.

He said the Angolan government apparently uses revenues from commercial food imports to step up imports of military hardware to fight UNITA forces.

"Although we're willing to take part in any emergency relief effort to aid people and governments genuinely incapable of dealing with the danger of imminent famine," Redman said, "we believe at the very least the situation in Angola deserves a much closer look before a decision on increased emergency relief is taken."