The mother of Irish rock legend Phil Lynott has objected to the Mitt Romney campaign using Thin Lizzy's music at last week's Republican National Convention.

Philomena Lynott said her son would not have approved of the US Republicans playing the Thin Lizzy anthem "The Boys Are Back In Town" at Romney's nomination as presidential candidate.

She said that the late Thin Lizzy front man would have rejected any association with the Republicans particularly the Christian right wing of the party.

The Dublin woman told the Irish music magazine "Hot Press" that she was upset that one of her son's most famous rock songs was used by the Republicans to endorse Romney and his running mate Paul Ryan.

The Thin Lizzy singer would have opposed the Republican anti-gay and pro-rich policies, she said. Instead she believed her son would have backed Barack Obama.

She told the magazine: "As far as I am concerned, Mitt Romney's opposition to gay marriage and to civil unions for gays makes him anti-gay – which is not something that Philip would have supported. He had some wonderful gay friends, as indeed I do, and they deserve equal treatment in every respect, whether in Ireland or the United States.

"Neither would Philip have supported his policy of taxing the poor and offering tax cuts to the rich, which Paul Ryan is advocating. There is certainly no way that I would want the Lynott name to be associated with any of those ideas.

"There is nothing I can do about it except express my views," Philomena Lynott added, "but I do want to be clear that I would not want Philip's music to be used in any way that could hurt a single person, and this is the effect of what happened with Paul Ryan using and abusing my son's music in that way. A lot of fans and musicians are very angry about it and I can fully understand why.

"There is a black president of America, which to me – as it would have been to Philip, as a proud, black Irishman – is wonderfully symbolic.

I have a lot of time for Barack Obama, so to hear 'The Boys Are Back in Town' being appropriated by Mitt Romney and Paul Ryan in their campaign against him is deeply upsetting."

The now 81-year-old Philomena Lynott wrote a best-selling autobiography My Boy about the extraordinarily difficult times she and Philip endured in the UK and Ireland at the beginning of the '50s, following Philip's birth in 1949.