M People founder Mike Pickering has said the band are “livid” that their song was used by Prime Minister Liz Truss on stage.
Ms Truss walked on to the stage at the Conservative Party conference to their 1990s hit Moving On Up, which features vocalist Heather Small, ahead of delivering her keynote speech.
The dance anthem, which was released by the Manchester-based band in 1993, peaked at number two on the UK singles chart.
Pickering told the PA news agency: “They (the band) are livid. Heather’s boy James is a Labour councillor. Hopefully most people will know that they have pirated it off us.
“She won’t be around to use it again for very long. I would imagine.”
He added: “I am absolutely gutted by it because they are killing the live touring of bands and artists… I am Mancunian and getting from Manchester to London these days is harder than getting on to continental Europe.”
Pickering said the band had contacted their lawyers but been advised there was little that could be done.
He said: “The rest of the band have rung me: ‘For God sake, how can we stop it?’
“And we just rang the lawyers and they went, ‘You can’t actually stop it. We can send a letter to cease and desist but you can’t do it’.
“They can play what they like, which seems a bit weird to me.”
Ms Truss entered to the track’s famous chorus “Movin’ on up, nothin’ can stop me. Movin’ on up, you’re movin’ on out. Time to break free, nothing can stop me.”
The opening lyrics of the song read: “You’ve done me wrong, your time is up”, with the last line of the first verse saying: “Move right out of here, baby, go on pack your bags”.
The son of the group’s lead singer Heather Small, James Small-Edwards, was elected as a Labour councillor for Bayswater, west London, in May.
Following Ms Truss’s entrance, he tweeted: “An apt choice! This tired and out of touch Tory Government is indeed moving on out.”
Small has also previously shown her support for refugee charity Care 4 Calais’s #StopRwanda campaign.
Boris Johnson previously used Friendly Fires’ track Blue Cassette as he walked out for the party conference last year.
The indie band later hit out at the then-prime minister, saying their “permission was not sought” to use the song and that they had asked their management to ensure it was not to be used again by the party.
