The State Department dismissed a Soviet protest Friday over the expulsion of a diplomat accused of spying and said that Lt. Col. Yuriy Pakhtusov will be leaving as ordered.

The State Department and the Soviet Foreign Ministry differed on the impact of the incident on Soviet-American relations.A Soviet spokesman said that the expulsion order was the work of "certain circles" working to sabotage better relations between Moscow and Washington and "is incompatible with the new atmosphere."

State Department spokesman Charles Redman said, "There is no reason to believe it should affect our relationship. The Soviets know, as they always have, that we will protect our security whenever it's threatened."

Soviet Foreign Minister Eduard Shevardnadze and Secretary of State James Baker agreed this week to meet in Moscow in early May to set the date and the agenda for a U.S.-Soviet summit conference this year.

According to the FBI, Pakhtusov was arrested Wednesday night near his northern Virginia home while receiving classified documents from an employee of a defense contractor. The information in the documents concerned the ways that the government safeguards classified information in its computer systems.

Foreign Ministry spokesman Gennady Gerasimov said in Moscow Friday that Pakhtusov was arrested while chatting with an American friend at the friend's apartment in the building where Pakhtusov lives.

"The FBI agents forced their way into the flat and despite Pakhtusov's protests that he has diplomatic immunity and can document his identity, he was subjected to physical force and put in handcuffs," Gerasimov said.

"This is a gross provocation by the U.S. security services," Gerasimov said. "The United States will have to assume the responsibility for what comes in the future," he said without elaborating.

Redman said, "The reason for our action was very simple. He was caught red-handed with the goods, and no amount of verbiage can change that."

Gerasimov, by suggesting there will be some future Soviet action, hinted that there will be retaliation against an American diplomat in Moscow. Both governments agreed in February to increase the size of their embassy staffs by 15 people immediately and another 26 by August to take care of the increased workload created by the larger number of diplomatic, cultural and business contacts between the Soviet Union and the United States.