One in six of all on-screen BBC roles must go to lesbian, gay, bisexual and transgender or disabled people by 2020, the corporation’s new diversity targets state.

In a bid to deter criticism that it has been failing to reflect its audience, the BBC has pledged that LGBT and disabled people will each make up eight per cent of all on-air and on-screen roles.

The new targets follow a heated debate in the House of Commons led by David Lammy MP on the issue of the broadcaster’s diversity.

The BBC’s new diversity targets follow a debate in the House of Commons led by David Lammy MP (pictured) on the issue of the broadcaster’s diversity

Fifty per cent of all on-screen and broadcasting roles will go to women, who already make up 48.5 per cent of the BBC’s total workforce.

However, the BBC will still be able to commission shows where the main roles are more likely to be male-dominated.

Radio 2, which has a particularly male-dominated line-up of broadcasters, including DJs and presenters Chris Evans, Simon Mayo, Jeremy Vine and Bob Harris, faces an overhaul.

Last year, a review by the BBC Trust, the corporation’s watchdog, found that six stations – including Radio 2 – raised concerns that they were failing ethnic minority audiences.