The British security service deemed black American singer Paul Robeson a security risk and tried to prevent him from entering the UK, according to secret Home Office papers released today.

The star, who died aged 77 in 1976, was regarded as a "nuisance" by MI5 because of his outspoken left-wing views and support for black civil rights.

Robeson visited the UK in 1949, and returned the following year, when MI5 agents tracked his movements.

But for much of the 1950s, the United States authorities refused the singer a passport.

The US came under strong international pressure to allow the star to travel freely - particularly from the UK, when Robeson was invited to star in Othello at Stratford-upon-Avon and speak at trade union rallies.

MI5 repeatedly advised against letting him into the country.

"Robeson, when last over here, was a security nuisance," noted a report from 1951.

"He is convinced that he has a mission to lead oppressed Negroes and colonial peoples everywhere. He is a fanatical communist and intensely ambitious."

Propaganda

MI5 believed that the British Communist Party would "do all in its power to exploit the visit for propaganda purposes".

Despite MI5's disquiet, Robeson visited the UK for a series of concerts when the US authorities restored his passport in 1958.

One Home Office official wrote: "Paul Robeson may be a communist, but he is also a great artist and a world figure.

"To turn him out of the country or to refuse him entry would create a major crisis."

Conservative Home Office Minister Patricia Hornsby-Smith was less than enthusiastic.

As a personal friend of Labour politicians Aneurin Bevan and Barbara Castle, "Robeson is going to give us a lot of trouble on African affairs", she said.

Sex scandal

The controversy surrounding Robeson is among a series of revelations to emerge from the papers released to the Public Record Office in London on Thursday.

MI5 also investigated the 1920s American actress Tallulah Bankhead amid rumours she was corrupting pupils at Eton public school.

And the UK refused to give asylum to the exiled Russian revolutionary Leon Trotsky for fear of offending his archrival, Josef Stalin.