LINGERIE entrepreneur Lady Michelle Mone has launched a new defence of her business affairs and said she has "not done anything wrong" when it comes to allegations of tax avoidance.

Lady Mone – who was made a Tory peer after being appointed start-up czar by Prime Minister David Cameron and will take her seat in the House of Lords today – is alleged to have avoided tax using a scheme of the kind branded "morally repugnant" by Chancellor George Osborne.

It emerged in August that the new Baroness Mone of Mayfair used employee benefit trusts or EBTs – the loophole that landed Rangers FC in court – before her high-profile but small bra firm suffered substantial losses.

Her company MJM International paid more than £500,000 in to EBTs when it was in profit, according to accounts filed at Companies House.

"I have not done anything wrong," she said in a magazine interview. "I use a big accountancy firm in Scotland. They've looked after me for 12 years. I have checked with them since the divorce – 'Have I done anything that I shouldn't have done?' 'Michelle, no.'

"And everyone knows my ex dealt with all the finance and dealt with all the lawyers. I was never, ever allowed to get involved in his side and he never got involved in my side."

The 44-year-old Ultimo co-founder from the east end of Glasgow insisted she would not have been allowed in to the House of Lords if she hadn't passed the necessary checks.

She also expressed surprise at being labelled a "Tory poster girl".

"I believe in what they're doing. But when I don't think they're doing a good job, am I still going to agree with them? No. They don't own me."

Lady Mone admitted some trepidation over her maiden speech which will take place later today, saying she had spent considerable time gleaning up on the rules of etiquette in the Lords.

"It's a huge thing," she said. "And it's all, 'My Lord, my – you can't say 'You'. My 'Fellow Lord'. I don't want to screw it up. I've been reading the manuals and I'm almost done."

But she spoke of her steely determination to succeed in her new role.

"I never, ever, will lose," she said. "If I have to work 10 times harder and put in more work than that person I will get past the finish line before them. And that's the way I have always been. And I'm never going to change.

"I don't work for the government. I'm doing this for free off my own back and it's all new to me and I'm out of my comfort zone."

Lady Mone also asserted that she tried not to let the words of her critics affect her.

"That's just life," she said. "I'm not one to sit with a box of tissues and cry myself to sleep.

But admitted: "The criticism – it's as if I have robbed a bank."

Her ex-husband Michael, with whom she has three children, is getting married later this month to former Ultimo head of design, Samantha Bunn, and Lady Mone insisted she "wishes him well".

It has been reported that Lady Mone has a new boyfriend in professional golfer Stefan Soroka, who works at the five-star Sandy Lane resort in Barbados.

She is quoted as saying: "I have never felt this way before."