Charlotte Church’s status as a prominent anti-austerity campaigner has taken another step after the singer announced she would happily pay tax at a rate of 70% if it would protect public services.

Church, who last month won praise for defending herself as a “prosecco” socialist after some media reports accused her of hypocrisy for protesting against cuts while being personally wealthy, was speaking at the launch of another anti-austerity demonstration on Thursday.

I may be a prosecco socialist, but at least I went out to protest | Charlotte Church Read more

The 29-year-old was asked if she would happily pay more tax to protect services. She replied: “I have paid all my tax since I was 12 years old, and I would certainly be happy if the rate was 60% or 70%. I wouldn’t move away, I wouldn’t have an offshore account.

“That would be totally fine, for better infrastructure and public services and more of a Scandinavian model, which I see as far more progressive than the way we are, I would be absolutely fine with that.”

Unite the union (@unitetheunion) Great to see @charlottechurch at the #EndAusterityNow demo launch | Join us all on 20 June - http://t.co/WMzOtsEf6s pic.twitter.com/hefqNhdSmA

Church was speaking in London alongside the Labour MP Rachael Maskel, the Green party’s deputy leader, Amelia Womack, and Steve Turner, assistant general secretary of the Unite union, to promote an anti-austerity protest planned for 20 June in central London, involving a march from the Bank of England to Parliament Square.

In May, Church joined a similar event in Cardiff. She said: “It was the first rally I have been on since I was nine and it was super fun for a start and it was amazing to be around lots of different types people from different walks of life who just have a common thread of empathy and it was inspiring to be with those people.

“A lot of the time when we think about the welfare state I think a lot of people think those people who are the most vulnerable in society are on benefits. But the welfare state is everything: it’s our fire service, it’s our NHS, our education, our travel, everything we have and we will all be affected by these cuts.

“And as soon as people realise the extent of it and how it really is going to affect all of us, I think there will be a lot of anger and a lot of discontent.”

Church was disparaging about David Cameron, saying she had experienced him as dismissive and sexist when she met him. She said: “I met Cameron at the party conference when I went with Hacked Off. He was gross and really misogynistic.

“All the men were opposite him, and me and [TV presenter] Jacqui Hames sat either side of him for the photo opportunity. He was so dismissive of what I had to say. It just really irked me that whole situation.”

Church reiterated that it was entirely legitimate for her to protest at the cuts while not herself being financially vulnerable: “Is it essential that I should have been through some personal suffering from the cuts to have empathy with everybody else? I don’t think so.”