Kamal Ahmed, the BBC's director of news, was found to have earned £12,000 from addressing a conference and forced to repay the money.

"It’s an outrage that people who make their profile at public expense should seek to give themselves further financial rewards and personal gain," the source said. "They’re basically making their names on the taxpayer and then cashing in. The BBC should immediately halt this practice and give the money to good causes."

However, critics have pointed out that BBC employees aren't the only ones using their outsized public profile to make money from speeches, consulting and more.

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So who are the biggest earners?

Boris Johnson

The Prime Minister's a career trajectory has taken him from journalism to MP, Mayor of London, and Cabinet minister - to the top job.

But his public prominence, built through everything from appearances on Have I Got News For You? to ziplining with Union Jacks in the build up to the Olympics, has meant that he's been able to cash in even while serving as an elected politician.

Where did the money come from? More than £400,000 came from speeches, charging an average of £20,000 per hour. One speech delivered in New Delhi in March 2019 was worth £122,900 on its own.

That was topped up by his £275,000-a-year Daily Telegraph contract as a columnist, something he has had to abandon as Prime Minister.

However, the outside benefits may not have entirely disappeared: Mr Johnson is facing questions over who paid for his £15,000 Christmas holiday to Mustique in the Caribbean. The parliamentary standards watchdog is looking into it.

John Redwood

The veteran Conservative Brexiteer has long been one of the best remunerated MPs, and not because of a ministerial brief - he's been out of cabinet since 1995.

Instead, Mr Redwood earns £15,606 per month from his role as the chairman of Charles Stanley, a wealth management company. It's an expected commitment of 50 hours, a week, so not insubstantial around parliamentary and constituency work - but he did get a bonus of £46,818 to cushion the blow.

Owen Paterson

The badger-chasing former Secretary of State for the Environment, Food and Rural Affairs has substantial monthly earnings from a variety of consultancy roles.

Randox Laboratories, a clinical diagnostics company near Belfast, pays him £8,333 a month for 16 hours' consulting, while Lynn's Country Foods, a sausage maker in Co Down. pays him £2,000 every second month for four hours' work.

He also consults with Hi-Peak Feeds, near Sheffield, for £4,166 a month for 8 hours' work.

Jacob Rees-Mogg

When Jacob Rees-Mogg went from a backbench MP to Leader of the House of Commons under Boris Johnson, he earned a pay rise of almost £80,000 a year. That won't make an enormous amount of difference to his daily life, however - he already has plenty of other sources of income.

Mr Rees-Mogg is a partner in Somerset Capital Management, a wealth management company, for which he received more than £15,000 a month for up to 30 hours a month work in the last register of interests.

Apart from his part time role managing money, he has capitalised on his media profile in a variety of ways, earning between £250 and £520 a piece for several articles for the Daily Telegraph and The Times, in addition to £9,600 for presenting a show on LBC.

He also received £10,000 for several speaking engagements, and a total of £26,000 for writing, publishing and recording an audio version of his book, The Victorians - a total of 322 hours.

Ed Davey

It's not only prominent Conservatives who can make money outside their job: Lib Dem deputy leader (and leadership hopeful) Ed Davey also has a lucrative set of entries in the register of members' financial interests.

He chairs Mongoose Energy, which develops community owned renewable energy schemes, earning him £5,000 every three months. On top of that, there's consultancy for business services firm Herbert Smith Freehills (£5,000) a month, and more renewables work for the board of Next Energy Capital, a solar power investor, which pays £4,500 every three months.

Tom Tugendhat

The Tory up and comer's list of interests is a land of contrasts: £250 for a Daily Telegraph article one minute, then £135,000 for leadership advice for management consultant Lashkar & Co the next. Another course of advice at the firm earned him another £100,000.

MPs who make the most from side jobs as Downing St weighs up BBC speech ban