Heather Mills McCartney went on a TV offensive for a second day today, criticising Sir Paul McCartney for not speaking out against articles which led to her receiving death threats.

The estranged wife of Sir Paul, 65, followed up her British appearances yesterday with an interview on America’s Today show.

She said she told the former Beatle he needed to stand up and take responsibility for the breakdown of their marriage.

Mills McCartney, 39, said she promised him she would “walk away with nothing” in a “very gentle and quick divorce” if he did that, but she said he “did nothing”.

In an emotional interview with the NBC programme, the former model said: “All I can say is when we first split, I said to Paul ’I’m going to be crucified. You know why we split. You know the truth. They don’t need to know the details, but you need to stand up and say ’I’m responsible for the breakdown of this marriage’.

“’If you say that, I’ll walk away with nothing, and we’ll do a very gentle and quick divorce.’ And he promised he’d do that. I have evidence of that. And he did nothing.”

Asked who she thought was behind the death threats, Mills McCartney told NBC: “Well, I can’t say who I think it is because it will affect our family, but I know a lot of information and, you know, certain people don’t want certain things coming out because of their image.”

She also continued her criticism of the tabloid press for “putting front-page news about divorces instead of front-page news about global warming and important issues”.

She told NBC there were “so many” lies told about her.

“They say I’m a fantasist, a liar, a whore, everything you can possibly think of is being said and it’s just, it’s outrageous. It’s so hurtful man.”

She went on: “And the problem in England is with the libel, there is a cap on costs and damages.

“So they will get six months of abusive lies front-page news out of you, and then they will only have to pay 50,000 dollars to 100,000 dollars damages.

“In the meantime, they’ve created devastation everywhere, and you get an apology the size of a postage stamp.”

She went on: “I fell in love with a man, not a Beatle. I fell in love with someone that chased me for three months, that people forget, that wooed me, that was a broken man when I met him.

“And everybody around him knows he wouldn’t perform, he hadn’t performed for a long time. If actually someone sat down and did their proper research and looked at the facts, I was a huge support for Paul.

“I put all my own work, except my charity, on hold for the seven-and-a-half years we were together.”

Yesterday, in British TV interviews, Mills McCartney compared herself to Princess Diana and Gerry and Kate McCann, and accused Sir Paul of stalling on their divorce settlement.

Crying and with her voice breaking as she leaned forward in her seat, Mills McCartney also attacked the tabloid press.

She choked back tears and put her head in her hands while attacking the media for subjecting her to the same treatment as Diana.

She pledged to campaign to change the press laws, and said she had received death threats and wondered whether she might be “revered” like Linda McCartney if the “death threats came true”.

Mills McCartney met Sir Paul in 1999 at a charity event and they married at a remote countryside castle in Ireland in 2002.

She gave birth to the couple’s child, Beatrice, in the autumn of 2003 and the pair announced their separation in May last year.

The most sensational claims made during Mills McCartney’s acrimonious break-up with Sir Paul came in an extraordinary document widely believed to have been leaked to the media by the Mills McCartney camp.

The document - which she denies leaking - made a series of remarkable claims about the ex-Beatle’s behaviour during their five-year marriage.

There were also claims that Sir Paul changed the locks at the marital home, froze her bank account and removed £10 million-worth of paintings from her house.

A Government minister tonight said he felt sorry for Mills McCartney, who appeared to be “a woman very much on the edge”.

Innovation and skills minister David Lammy told BBC1’s Question Time he found it “disturbing” to watch Heather in her TV appearances over the past few days.

Mr Lammy said: “I did feel actually quite sorry for her. I do think she is a woman very much on the edge.

“It was actually quite disturbing to watch and I hope that perhaps she seeks the right support because it’s not nice to see someone who clearly is losing themselves to the media frenzy surrounding them and, in the end, a marriage that is breaking down.

“And she does have a child, so I do feel for her in that sense.”