THERESA May has remained tight-lipped after topping a list of MPs that earn money outside their parliamentary work.

An analysis conducted by Sky News and Tortoise found the Maidenhead MP had declared the most in donations, earnings, gifts, and other benefits worth approximately £2.8m since the 2019 general election.

She took home £2.5m on top of her parliamentary salary, mainly from giving various speeches in America. Mrs May received £408,200 from the Cambridge Speak Series and £160,700 from JP Morgan Bank.

However, she draws £85,000 from this pot and the rest of the money goes towards paying for her private office, promotions of her public life and charitable donations.

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The Conservative MP beats other well-known recipients, such as former Prime Minister Boris Johnson, who received more than £1m since October for just giving four speeches.

Mrs May’s office declined to comment after the Local Democracy Reporting Service approached for comment.

However, Business Secretary Grant Shapps, who voiced support for MPs in having second jobs, defended Mrs May, saying she is a good MP.

He added the former Prime Minister is "one of the most effective constituency MPs there is" and that she is a "hot ticket" on the speeches circuit.

Windsor’s long-standing MP Adam Afriyie only has one registered interest listed in this analysis. He received one gift worth £10,330 from the Global Tobacco and Nicotine Forum trust.

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A spokesperson for the Conservative MP said Adam represented the UK at a conference in the US in September 2022, during recess, and the register reflects the transport, visa, food, and accommodation costs for that event.

He did not receive any payment for speaking at the conference, the spokesperson added.

They also said: “More broadly, while Members of Parliament have duties and responsibilities to represent their constituents both in the constituency and in Westminster, they have historically also been paid for roles outside parliament such as front bench spokesmen, government ministers, healthcare practitioners and as professional advisors, and for media appearances, newspaper articles, survey completion and sometimes as authors or for union associated work.

“Outside roles tend to add to expertise and perspective and can enhance the effectiveness of an MP”.