WASHINGTON (AP) _ Sens. John Kerry and Bob Smith said Wednesday they will visit Moscow next week seeking information about alleged Soviet interrogations of American prisoners during the Vietnam War.

Kerry, D-Mass., and Smith, R-N.H., the leaders of the Senate's Select Committee on POW-MIA Affairs, said they will meet with current and former officials of the KGB and Defense Ministry and with other sources uncovered by committee investigators.

During his recent trip to the United States, Russian President Boris Yeltsin pledged to help open archives that may contain information about Soviet involvement with American POWs. Last week, Kerry and Smith met with Russian parliament officials on the formation of a U.S.-Russian joint commission to examine the fate of POWs and soldiers listed as missing in action who never returned.

''It is becoming clear to us that Soviet files may hold important clues about what happened to American servicemen,'' Kerry said. ''We are building a case the Russians cannot ignore, and this trip will help us test their ability and willingness to cooperate.''

The two will be in Moscow from Feb. 13-17.

Smith said sworn testimony from former Vietnamese, American and Soviet officials points to Moscow as a source of further information.

''There never will be a better time for the Russians to show their good faith by helping us learn the fate of our missing servicemen,'' Smith said.

Last month, Maj. Gen. Oleg Kalugin, a former top KGB official, told the Senate committee that the spy agency interrogated American POWs in Vietnam as late as 1978. Kalugin also testified that the Defense Ministry probably had even more involvement with American POWs.