Moscow has followed through on a pledge to upgrade the status of the Palestine Liberation Organization office, but has stopped short of recognizing a full-scale PLO embassy.
A Soviet official noted privately that Moscow's announcement of the upgrading late last year spoke only of extending ''official diplomatic status'' to the mission, previously listed as ''accredited with the Soviet Afro-Asian solidarity committee.''
The official says Western analysts were wrong to equate the change with recognition of a full embassy. The Soviets, long bidding for reentry into the Arab-Israeli negotiating arena, officially recognize the state of Israel. The PLO, the official noted, is ''not a state.''
The distinction was evident in official coverage of an April 30 meeting between Soviet Foreign Minister Andrei Gromyko and ''the head of the mission of the Palestine Liberation Organization to the Soviet Union.'' The meeting, according to a report from the official Soviet news agency, was ''in connection with the granting to the PLO mission of an official diplomatic status, and its accreditation at the USSR Foreign Ministry.''
The Soviet official said the PLO representative had, in effect, presented his credentials to Mr. Gromyko. Full state ambassadors, the official noted, would normally present credentials to Vasily Kuznetsov, Mr. Brezhnev's largely ceremonial deputy as Soviet President.