LONDON (Reuters) - British pop star George Michael (news) appears on the BBC's "Top of the Pops" program on Friday for the first time in 17 years, but the studio filming of his anti-war song did not go off without a hitch.

A spokeswoman for the pop star said Michael recorded a cover of Don McLean (news)'s "The Grave" -- first released during the Vietnam War -- for Friday night's show. But it was Michael's four female background musicians who attracted most attention, the spokeswoman told Reuters.

They all sported anti-war T-shirts with "No War, Blair Out" messages on them, the same as those showed by British designer Katharine Hamnett during last month's London Fashion Week.

"The producers asked them to take them off, which caused George to have a heated argument with the producer and the girls did wear the T-shirts in the end," the spokeswoman said. "But this evening on the performance they will probably be bleached-out or blacked-out in some way."

A "Top of the Pops" spokeswoman said however that, while producers were not happy with the T-shirts, Michael and the executive producer Chris Cowey did not argue and the atmosphere was very friendly.

"At the end of the day it's a slightly tricky issue having big T-shirts with slogans on them, saying 'Blair Out, No War' but having seen part of the editing process today you can't see the T-shirts on the show anyway," she added. "If you could have seen them, we would have worked around them. They were cellists anyway and the instruments were covering half of the shirts."

Michael chose McLean's 1971 song "The Grave" to express his feelings about a possible U.S.-led war on Iraq (news - web sites), something he has done before.

Last year, he angered Americans with a single called "Shoot the Dog," mocking President Bush (news - web sites) and his War on Terror.

Earlier this year, Michael allowed Brit award winner Ms Dynamite to rework his hit "Faith" to include an anti-war rap during her performance of the song at the Brits, the annual Oscar ceremony for the British music industry.

McLean said: "I am proud of George Michael for standing up for life and sanity. I am delighted that he chose a song of mine to express these feelings."

Michael shot to fame in the 1980s as part of the band Wham!. He last starred in "Top of the Pops" with Wham!'s number one hit "Edge of Heaven" in 1986.