WASHINGTON (AP) _ A Soviet defector has been telling U.S. government agencies some of the inner secrets of a little understood Kremlin body that plays a key role in charting Soviet foreign policy.

Under Soviet leader Mikhail S. Gorbachev, the International Department of the Communist Party Central Committee has shifted course, loosening its ties with Marxist parties in the West and cultivating relations with other less radical elements, said the defector, Evgeny Novikov.

''Gorbachev started to promote the principles of his 'new thinking,' to find new clients, sometimes at the expense of old clients, to find parties and groups that have influence in capitalist countries,'' Novikov said in a recent interview with The Associated Press. The new approach has brought closer Soviet ties to American and Western European environmental and peace groups that agree with Gorbachev's approach to disarmament and attempts to lessen international tension, said Novikov.

Because his work in the International Department centered on Arab and Middle Eastern affairs, Novikov declined to speculate on which Western groups were sympathetic to Gorbachev's new approach.

U.S. intelligence officials, who said they were not familar with the specifics of Novikov's case, confirmed that Novikov's description met their understanding of the International Department.

They said most U.S. and Western European groups were sophisticated enough to remain independent even while developing contacts with Soviet officials known to be linked to the International Department.

The International Department, for which Novikov worked from 1970 until his defection last year, was the successor to the Comintern, or Communist International, or later the Cominform, disbanded by Josef Stalin in 1947.

The Comintern was the main organ of Kremlin influence on communist parties outside the Soviet Union, a means of molding political platforms and sometimes recruiting intelligence agents, according to numerous accounts by defectors.

The International Department shares with the Foreign Ministry responsibility for formulating Soviet foreign policy, which is decided by the ruling Politburo, Novikov said. The Foreign Ministry carries out state-to- state contacts, while the International Department handles party-to-party matters.

Senior International Department experts are driven in chauffeured cars, receive salaries equal to those of deputy ministers and have access to intelligence reports from the ministries of defense and foreign affairs, and the KGB, Novikov said in a paper prepared for the U.S. government.

Shortly after Gorbachev rose to power in March 1985, he tried to gain control of the International Department and change its inner workings by appointing as its chief Anatoly Dobrynin, who had served as the Soviet ambassador to Washington since the 1960s.

''Dobrynin, however, was very much an outsider'' to the Moscow bureaucracy, Novikov said. Thus Dobrynin's reform attempts foundered, forcing Gorbachev to move him from the Central Committee Secretariat into a newly created post as adviser.

''The old timers in the International Department opposed Dobrynin,'' said Novikov. ''The old cadres sabotaged Dobryinin.''

Last fall, Gorbachev reorganized the Central Committee Secretariat, naming his right-hand man, Aleksandr Yakovlev, as head of a newly created International Commission, which controls the International Department.

The new head of the International Department is Valentin Falin, a former ambassador to West Germany.

Before the reorganization, said Novikov, many of the senior officials in the International Department dated back to the days of Mikhail Suslov and Boris Ponomarev, two Stalinist holdovers who served under the late Soviet leader Leonid Brezhnev.

Novikov lectured from 1970 to 1985 in the Institute for Social Sciences, which he described as a secret school run by the International Department in Moscow. His job was to conduct seminars in political philosophy for small groups of students from Marxist parties in South Yemen, Syria and Iraq and for two radical Palestinian groups, the Democratic Front for the Liberation of Palestine and the Peoples Front for the Liberation of Palestine.

Professors at the institute drew up classified reports on those movements, based in part on what the students said in class.

''For example, I made a study of the Yemeni Socialist Party, its origins, history, influence of Marxism, influence of Islam, influence on the masses,'' said Novikov.

From 1985 until his defection, Novikov was chief of the Arabic editorial office of the World Marxist Review in Prague, Czechoslovakia.

Arabic versions of the magazine ''were printed mostly in Western countries, and distributed in various Arab countries under titles very different from the original.

''The goal was to pretend it was a national magazine, produced in each nation, but 70-100 percent of it was prepared in Prague ... under directions from the International Department,'' said Novikov. ''Nowhere did it say it was printed in Prague. One percent of the readers would know where it came from.''

Novikov crossed the border in Austria in March 1988, was given asylum by the U.S. Embassy there and spent the next seven months briefing Western officials.

Novikov, who has the Soviet equivalent of a doctorate, has been living in the United States since last September, working as a butler in a small hotel while he tries to launch a career as a consultant in Soviet affairs.

In contrast to past Soviet defectors who complained about insensitivity on the part of their CIA handlers, Novikov said he ''met with a very human attitude from the United States government.''

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