LONDON, NOV. 18 -- A ghost from the past reappeared here today, with the broadcast of a recent Soviet television appearance by Britain's most infamous 20th century traitor, Kim Philby.

Philby, 75, escaped to Moscow in 1963, after 30 years of spying for the KGB while working in some of the British intelligence service's most senior and sensitive posts. Since then, he is not known ever to have made a television appearance, and has given only one substantive interview to a western journalist, in 1968.

The news item showed Philby in an interview that originally appeared Oct. 11 on regional television in Latvia, one of the three independent Balkan states forcibly incorporated into the Soviet Union in 1939. The interview, in which Philby alleges western intelligence penetration of Balkan emigre organizations, was part of a series of programs designed to discourage anti-Soviet demonstrations in Riga, the Latvian capital.

In its excerpt of the interview, the British Broadcasting Corp. largely ignored what Philby said, concentrating on his appearance. Dressed in a tweed suit with an English-style knttted vest, he wore tinted glasses. Several of his front teeth were missing, and two canes leaned behind the armchair in which he was seated.

The interview, voiced over by a Latvian translation, was conducted in English by a man the BBC identified as a "KGB colonel" who addressed Philby as "Comrade Kim." In one portion in which the English can be heard, Philby chides his interviewer for asking a "simplistic question."

Considered the most successful double agent of the Cold War, Philby served in Washington as liaison between the CIA and British intelligence in 1949-51. He was removed from that post after the defection to the Soviet Union of two other British double agents, Guy Burgess and Donald MacLean. Although U.S. officials suspected Philby was the "third man" of a Soviet spy ring, and pressed for an investigation, many in Britain felt he was being victimized by U.S. McCarthyism, and he was allowed to retire quietly.

By 1956, however, Philby was again on the payroll of MI6, the British intelligence agency, and was sent to Beirut under cover as a journalist. He disappeared in 1963, and reappeared six months later in Moscow.

Early U.S. suspicions and final proof of Philby's treason were considered responsible for what became an atmosphere of suspicion between American and British intelligence services.

Philby has long been a subject of fascination in Britain. One of a group of Cambridge and Oxford University students who turned to communism in the 1930s, Harold Adrian Russell Philby was considered by some a prime example of ideological decadence of the upper classes.

Major profiles and tidbits from rare Philby sightings in Moscow are staples of British newspapers even today. The last time any British correspondent reported seeing him was in 1978, when Daily Telegraph reporter Richard Beeston ran into Philby and his fourth wife, a Russian, at the ballet.

Earlier this year, writer Graham Greene, who served under Philby in British wartime intelligence and has carried on a sporadic correspondence with him for some years, was publicly lambasted in the press here for what were described as several "secret meetings" with Philby in Moscow. Greene said the encounters had been mostly by chance, and always within a group of people.

But although Philby has shunned his former countrymen in Moscow, he reportedly has kept up on things British over the years. Every few years, he writes to a British newspaper, correcting alleged mistakes in spy books. According to some accounts, the Soviet Embassy videotapes televised cricket matches and sends them to him.

Despite the amount of coverage he has long been accorded in the country of his birth, it is only recently that citizens in his adopted land have learned of his exploits on their behalf. It was not until 1980 that his memoirs, published in the West in 1968, were published in the Soviet Union.

It was also in 1980 that the Soviet news media first interviewed Philby and published a major account of his life. Hailing him as a "wonderful man," the interview in Izvestia noted that he "remains at his combat post," and that he had been awarded the People's Friendship Order in addition to his Order of Lenin and Order of the Red Banner.

Unlike some other Soviet double agents who came in from the cold, Philby is reported to have lived well in Moscow since his 1963 arrival there. According to western accounts, he has worked as a senior adviser to the KGB, and holds the rank of colonel.

According to one published account in Latvia, Philby is now filming a four-part series on his life as a spy, to be entitled "The Game."