Clive Lewis a Labour MP for Norwich South, was once a senior broadcast journalist and the main reporter on the BBC’s Politics Show East.

Mr Lewis spoke at a Momentum rally in September of last year, and his comments were unearthed in a secret recording, and will come as a huge embarrassment to the BBC, which has already been criticised numerous times for its perceived bias.

He said: ‘I was able to use bias in my reports by giving less time to one than the other.

‘I reported on both but the angle and words and the language I used — I know the pictures I used — I was able to project my own particular political positions on things in a very subtle way,’ which was reported by the Sun on Sunday.

Tory MP Damian Collins said: “He’s boasting about undermining one of our great institutions.”

A spokesman for Mr Lewis declined to comment. A BBC spokesperson said: “Our editorial guidelines ensure impartiality.”