The Scots actor issued a statement after a video emerged online from the event, in which he appeared on stage singing Daniel Boone's 1972 hit Beautiful Sunday.
But today he said he had been singing the original lyrics to the song, which has featured in Still Game.
Mr Compston was joined at the event by fellow actor Gianni Capaldi and ex-Celtic players Alan Thompson and Bobby Petta.
In a statement released via his social media accounts, Mr Compston said: “Not best pleased to wake up to a story 8 hours ahead of me before I've had the right to reply.
"Let me be absolutely clear, I unequivocally did not sing ANY sectarian songs.
"I've worked in Belfast too long to see damage done to think this stuff is a laugh.
"If people want to change lyrics to a song that's sung at Celtic Park, weddings, Still game wherever that's up to them I'm not the lyric police.
"If it was an IRA song and I was onstage bobbing along I would understand the story but I'm pretty sure Daniel Boone had nothing more than Beautiful Sundays in mind when he wrote the song and that's what I was singing.”