David Cameron's efforts to keep fit while in power were helped by more than £21,000 of discounts from a personal trainer, official records show.

He declared 150 cut-price sessions from trainer-to-the-stars Matt Roberts as donations during his time as prime minister.

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Mr Cameron was photographed on several occasions running with Mr Roberts, who claims to work with some of the "most famous physiques" in fashion, music, politics and industry.

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The former PM said the latest batch of 50 sessions from London-based Matt Roberts Personal Training were discounted by £7,500, or £150 per session.

The register of MPs' financial interests shows the donation was received and accepted on June 21 - two days before the EU referendum, the result of which saw Mr Cameron resign as PM.

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This follows a similar £7,500 discount for 50 sessions in January 2013, £3,625 for 25 sessions in December 2011 and £3,250 for 25 sessions in November 2010.

The overall total from the declarations amounts to £21,875.

Mr Cameron's wife Samantha received a discount of £85 per session for 10 sessions in December 2011.

In each case, Mr Cameron gave money to a charity of Mr Roberts's choice in return.

The Witney MP wrote in his most recent entry to the register: "Discount of £150 per session on 50 sessions of personal training received since April 2013; total value £7,500. I have made a personal donation to a charity of my trainer's choice."

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Mr Cameron became PM in May 2010 when a coalition government was formed with the Liberal Democrats before his party won power outright in May last year.