Diane Abbott has accused BBC Question Time of legitimising racist abuse after claims that the shadow home secretary was singled out before and during Thursday night’s episode of the political discussion programme.

The Labour politician claimed she had been unfairly mocked in the warm-up and had been interrupted more often than other panellists by Fiona Bruce, the programme’s new chair.

“We are appalled by the treatment of Diane Abbott on BBC’s Question Time,” a spokesperson for Abbott said. “It was clear that a hostile atmosphere was whipped up, propped up by reports of inappropriate and sexist commentary in the audience warm-up session.

“A public broadcaster like the BBC should be expected to be a model of impartiality and equality. The BBC cannot claim anything of the sort when analysis of the programme shows that the only black woman on the panel was jeered at and interrupted more times than any other panellist, including by the chair herself.

“The media must stop legitimising mistreatment, bias and abuse against Ms Abbott as a black woman in public life. The BBC should be ashamed that their programming is complicit in such behaviour.”

Audience members who attended the filming of Question Time in Derby claimed that the warm-up for the programme included innuendo about Abbott’s past relationship with Jeremy Corbyn and that the audience booed her name when it was announced.

The audience loudly applauded when she was asked about Corbyn’s refusal to engage in Brexit talks with Theresa May unless the prime minister ruled out a no-deal departure from the EU.

Abbott’s staff suggested the warm-up had “set the whole audience up to be quite negative” about the politician, while pointing at online viral videos suggesting Bruce had interrupted Abbott more than the other panellists.

A BBC spokesperson said the corporation had been in touch with Abbott’s team but suggested some of the claims about the show’s treatment of her which went viral on social media are false. “We are sorry to hear Diane Abbott’s concerns over last night’s edition of Question Time and we have contacted her team today to reassure them that reports circulating on social media are inaccurate and misleading. Diane is a regular and important contributor to the programme … we firmly reject claims that any of the panel was treated unfairly either before or during the recording.”

Question Time and other BBC current affairs programmes have become a lightning rod for claims of media bias against Labour, with the corporation repeatedly forced to defend aspects of its presentation of political topics.

The Momentum campaign group launched a petition demanding the BBC apologise after Bruce backed claims that Labour was behind in the opinion polls.

The Momentum petition referred to an exchange where panellist Isabel Oakeshott said that Labour were “way behind in the polls” and Abbott replied that “we are kind of level-pegging” before Bruce said that Labour were “definitely” behind. But recent polling has found the two parties roughly neck and neck.

Abbott has appeared on Question Time at least 29 times over several decades, according to her office. In a 2017 article for the Guardian, she described her experience as one of the UK’s first black MPs, highlighting the level of abuse she received on social media.

“I went into politics to create space for women and other groups who have historically been treated unfairly,” she wrote. “Once, the pushback was against the actual arguments for equality and social justice. Now the pushback is the politics of personal destruction. This is doubly effective for opponents of social progress. Not only does it tend to marginalise the female ‘offender’, but other women look at how those of us in the public space are treated and think twice about speaking up publicly, let alone getting involved in political activity.”