Novelist and former MP Lord Archer is selling more than 100 works of art from his personal collection at an auction which is expected to raise about £5 million.

He will also auction off what he describes as “personal mementoes” in a separate sale with the proceeds going to charity.

Among the lots offered at the first sale on June 27 at Christie’s in central London is a stopwatch used to record Roger Bannister’s first four- minute mile in 1954.

Lord Archer said: “I recently celebrated my 70th birthday – an event which prompts a certain degree of thought and realisation. As a result, I have begun to restructure my art collection with a view to the future.

“At Christie’s in June, I will host an evening gala auction with all proceeds benefiting charitable causes. This will include personal mementoes that I have acquired over the years and is the ideal opportunity to highlight many great causes that are close to my heart.

“The commercial auction the following day will offer works of art from my personal collection as well as works from the Neffe Gallery, of which I was, for three decades, a business partner.

“I have always enjoyed being an art collector and amateur auctioneer, and these two events allow me to celebrate both.”

Among the 150 works that will be sold are a portrait of Marilyn Monroe by Andy Warhol valued at about £150,000 and a painting by French impressionist Claude Monet which is expected to raise about £1.2 million.

The author of a series of best-selling novels, Lord Archer spent five years in the House of Commons as a Conservative MP.

He was imprisoned in 2001 after an Old Bailey jury found he lied in a libel action he had brought against The Star newspaper 13 years earlier, in which he was awarded £500,000 damages.