MPs have called on the BBC to reveal its legal costs in countering claims of equal pay and race discrimination.
BBC director-general Tim Davie has been asked to provide further information about the sums.
The Digital, Culture, Media and Sport Committee (DCMS) said it was “disappointed” by answers previously given on the issue.
It has now penned a letter to the BBC boss asking for information.
DCMS committee chair Julian Knight said: “It is disappointing that the BBC is unable to give answers to our questions about how much it has spent fighting claims of equal pay and race discrimination.
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“We know that the broadcaster has comprehensive internal accounting procedures and find it difficult to understand why it is unable to provide such a breakdown.
“We are keen to understand, at the very least, the minimum cost of these cases to the BBC and look forward to further information being provided.”
The BBC supplied supplementary evidence following its appearance before the committee in September.
The letter to the broadcaster comes after a watchdog investigation found no unlawful acts of pay discrimination at the BBC, despite high-profile payouts to female staff.
Critics labelled the Equality and Human Rights Commission (EHRC) report a “whitewash”.
High profile cases have included Newswatch presenter Samira Ahmed winning a sex discrimination equal pay claim against the broadcaster at a tribunal.
Broadcaster Carrie Gracie was also given an apology and back pay after resigning from her position as China editor in 2018 in protest at pay inequalities.
The BBC has made over 500 pay revisions for women in recent years – although it said the majority of these are for “fair pay” so are not to do with gender.
According to the committee, the BBC said it was unable to provide a breakdown on its spending on claims because in-house lawyers were salaried and worked on a breadth of employment law issues. It was also unable to provide a total cost for external counsel fees.
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