Israeli researchers say they have uncovered a document showing Palestinian president Mahmud Abbas was a Soviet agent in the 1980s, but his office called it a smear campaign and pointed to suspicious timing.

The claim first emerged in a report by Israeli public television on Wednesday night citing two researchers studying documents from the so-called Mitrokhin papers stored in Britain at Cambridge University's Churchill Archives Centre.

The researchers, Gideon Remez and Isabella Ginor of the Truman Institute at Jerusalem's Hebrew University, said he was named as a KGB

agent in Damascus in 1983 under the codename “Mole".

Remez said Abbas was not simply labelled a "source or collaborator."

"It says explicitly regarding Abbas that he was a KGB agent," said Remez.

Abbas spokesman Nabil Abu Rudeineh told AFP it "falls under the framework of Israeli absurdities which we have got used to,“ calling it a "smear campaign."

He also alleged it was an attempt to derail a Russian peace initiative."It is clear Israel is troubled by the (Palestinians') strategic relationship with Russia and by the clear and announced Russian position, which is to solve the Palestinian-Israeli conflict on the basis on an independent Palestinian state and the right of self-determination for our people," Abu Rudeineh said.

Abbas was born in what was then British mandate Palestine, but his family fled to

Syria during the 1948 war surrounding the creation of Israel.

In 1980, Abbas was selected to sit on the Palestine Liberation Organisation executive committee. He had been in Moscow in 1982, where he studied for his doctorate, according to his online biography.

The Mitrokhin Archive, where the document was said to have been found, is based on files of the

Soviet spy agency KGB that were smuggled to Britain. Major Vasili Mitrokhin was a senior archivist in the KGB's foreign intelligence archive from 1972 until his retirement in 1984, and, disillusioned with domestic Soviet oppression, secretly copied information by hand, before defecting to Britain with it in 1992.

The report comes as Russian President Vladimir Putin seeks to organise a face-to-face meeting between Abbas and Israeli Prime Minister Benjamin Netanyahu.