Singer Charlotte Church has been branded a "champagne socialist" by the Conservatives' leader in Wales after she criticised the party's election win.
Ms Church told an anti-austerity rally on Saturday the UK had "masochistically condemned itself" to a Tory government.
She said she had felt "sick and gutted" by the general election result.
On Sunday, Andrew RT Davies told BBC Wales Ms Church's comments were "unfortunate and unbecoming".
The mother-of two, 29, addressed around 200 campaigners on Queen Street, Cardiff carrying a placard, which read she was "mad as hell".
Using a megaphone, she told the crowd: "This week the UK masochistically condemned itself to five more years of Tory rule.
"Without the Lib Dems to centre them they have no restraint, nothing to stop them destroying our welfare system, selling off our health services or even making constraints upon our democracy."
Labour's Welsh public services minister Leighton Andrews took to Twitter on Sunday morning to say "well done" to Ms Church.
But the Welsh Conservatives' leader described Ms Church and Mr Andrews as "champagne socialists standing shoulder-to-shoulder".
"At the end of the day, to denigrate the electorate, who has just spoken, within 48 hours of the election, is slightly unfortunate and unbecoming."
He added Welsh Conservatives had "never taken anyone for granted" and pointed out the party had enjoyed its best result for 32 years.
"We do not seek power," he said, "we seek responsibility."
Ms Church's rally appearance came in the wake of an attack she launched against the Conservative Party on Twitter, after the party secured a slim majority.
She said the reins of power had been "handed over to the bogey men".
Ms Church has been asked to comment.