LONDON (REUTERS).- British author and former parliamentarian Jeffrey Archer expects to raise over 5 million pounds ($8 million) when he sells works from his art collection including paintings by Claude Monet and Andy Warhol.

"I recently celebrated my 70th birthday -- an event which prompts a certain degree of thought and realization. As a result, I have begun to restructure my art collection with a view to the future," Archer said in a statement.

The auction, at Christie's in London on June 28, will comprise around 150 items including a portrait of Marilyn Monroe by Warhol valued at 100-150,000 pounds and a Monet landscape worth an estimated 800,000-1.2 million pounds.

On June 27, best-selling author and amateur auctioneer Archer will appear at a separate charity sale at which he will offer around 20 mementos, collectibles and works from his personal collection along with pieces donated by public figures.

Items up for bid at that auction include a stopwatch used to record a 1954 race in Oxford which saw British athlete Roger Bannister become the first man to run a mile in less than four minutes.

Some of the proceeds from the auction will go to the Cambridge University Hospitals NHS Foundation Trust, of which Archer's wife Mary is chairman.

Archer was a favorite of former Prime Minister Margaret Thatcher, served in parliament, was made a lord, has sold tens of millions of books and mingles with the rich and famous.

But he was jailed in 2001 after lying in a libel trial against a newspaper which said he had had sex with a prostitute, and served half of a 4-year prison term.

(Reporting by Michelle Martin; Editing by Steve Addison)