Diane Abbott, pictured on the BBC's Andrew Marr show last weekend, said it was 'curious' she had been singled out

Diane Abbott and Corbyn cheerleader Paul Mason have sparked a furious row by suggesting that Theresa May's jibes at her are racist - as it emerges she defied leader to make yet another disastrous TV appearance.

The shadow home secretary appeared to make the extraordinary claim after the Prime Minister raised concerns about her track record.

Now it has been revealed Ms Abbott defied Jeremy Corbyn’s office to appear on BBC's Andrew Marr show last week.

According to sources, Ms Abbott directly arranged with the programme's produced to appear on the television show.

When senior aides discovered the planned appearance, sources claim John McDonnell, the shadow chancellor, and Karie Murphy, Mr Corbyn’s chief of staff, both phoned Ms Abbott to persuade her to pull out.

A source told The Times: 'John McDonnell was furious at the prospect of Diane going on again. In the end they got Jeremy to phone her himself — but she . . . went ahead and did the interview, which was predictably awful.'

The Prime Minister, who has been campaigning in Dewesbury today, repeatedly mentioned Ms Abbot during BBC's Question Time last night

Ms Abbot has branded the Prime Minister's attacks on her 'desperate' and said it was curious that she was being singled out

During the BBC's Question Time election special last night, Mrs May repeatedly mentioned Ms Abbott.

She highlighted the Labour politician's previous doubts about the DNA database and a car crash radio interview in which she was unable to say how much a pledge to increase police numbers would cost.

But as the programme was going on a clearly furious Ms Abbott posted on Twitter: 'Desperate stuff by May. Claims I want to wipe DNA database clean. Never said that. Curious that she is singling me out for attack #BBCQT.'

She also quoted Mr Corbyn saying that 'a society that cannot challenge racism is a society heading for division'.

Corbyn cheerleader Paul Mason then waded in to spell out the allegation, tweeting: 'You know what. It's time somebody called out the dog whistle racism behind Tory insults to Diane Abbott and I just decided to do it.'

In angry shouting match with LBC presenter and former Tory parliamentary candidate Iain Dale on the BBC's Newsnight, Mr Mason said: 'What is this racism with Diane Abbott?'

But Mr Dale accused him of playing the 'race card' and said the only problem with Ms Abbott was that she was 'not fit to be home secretary'.

The shocking racism claim was also derided by senior Conservatives.

James Cleverly, who is defending the Braintree seat, pointed out that Mr Mason had hours earlier smeared the PM by suggesting she was 'too unwell' to campaign. Mrs May has Type 1 diabetes but it has not stopped her reaching the top of politics.

'You know what. It's time somebody called out the dog whistle sexism behind Paul Mason's insults to Theresa May and I just decided to do it,' Mr Cleverly responded on Twitter.

In angry shouting match with LBC presenter and former Tory parliamentary candidate Iain Dale on the BBC's Newsnight, Mr Mason said: 'What is this racism with Diane Abbott?'

Corbyn cheerleader Paul Mason then waded in to spell out the allegation against the PM and other Tories

Mr Mason said Ms Abbott was being targeted with 'dog whistle racism'

A clearly furious Ms Abbott appeared to level the extraordinary accusation at the PM in a tweet during the Question Time election special

Earlier, Mr Mason, a former Channel 4 and BBC journalist, raised Mrs May's health as he attacked her for refusing to take part in a TV debate earlier this week

'Is there something wrong with her?' he said on the BBC's Daily Politics.

'I think we're actually entitled to ask, is she unwell? What's wrong with her?'

Presenter Jo Coburn said: 'Are you really posing the question is she unwell?'

Tory Toby Young, who was also appearing as a guest, interjected: 'Are you really raising the prime minister's health?'

Mr Mason insisted: 'I'm asking, it's a legitimate question, what is wrong with Theresa May that she can't go live?'

Nigel Evans, who is defending Ribble Valley for the Tories on June 8, told MailOnline: 'It is absolutely appalling, it is an act of absolute desperation to even suggest that the Prime Minister's reason for not deciding to do some of the interviews is that she is 'unwell'.

Theresa May delivered a series of jibes at Diane Abbott during her appearance on the BBC's Question Time election special last night

Ms Abbott's allegation was greeted with scepticism by many on her Twitter feed - although some of her followers agreed

'It shows the depths to which they will go to try to get into power.'

Mrs May came out fighting in her appearance on the Question Time special with a vow to force through Brexit.

The Prime Minister insisted she had the 'balls to call an election' to ensure negotiations with Brussels were 'successful' as she came in for a fierce grilling from voters in the showpiece TV event of the campaign.

She warned that Jeremy Corbyn and 'Marxist' John McDonnell were relying on a 'magic money tree' and would be a disaster in government.

She was followed on the programme by Mr Corbyn - who went into meltdown as he was mauled by voters over his lack of commitment to the nuclear deterrent, plans for a massive spending splurge, weak stance on Brexit, and IRA links.

The Labour leader was jeered and heckled on a BBC election special as he repeatedly dodged saying whether there were any circumstances under which he would use Trident.

The veteran left winger's manifesto was also likened to a 'letter to Santa Claus', and he was grilled on how he would be able to negotiate effectively with Brussels when his position as PM would be reliant on the SNP and Lib Dems - who are desperate to water down the terms of our departure.

Asked about his IRA ties, including inviting convicted members to the Commons shortly after the 1984 Brighton bombing, the veteran left-winger condemned 'all acts of terrorism'.

But he again refused to condemn the IRA directly. One audience member said:' They did kill a lot of people didn't they?'

Mr Corbyn replied vaguely: 'All deaths are wrong, all killing is wrong.'