The landscape is expected to fetch up to �120,000 at Sotheby's

The oil sketch of Dedham Vale in Suffolk, where John Constable grew up, is expected to fetch around �120,000 at auction at Sotheby's.

The landscape was completed in about 1810 and was given to one of Constable's friends before being sold to a Japanese collector.

It was finally confirmed as a work by Constable after extensive cleaning.

A spokesman for the auction house said: "The work was sent to London, where it was cleaned by specialist restorer Sarah Cove.

"After cleaning, Constable's hand was immediately apparent, and soon after the work was fully accepted by Graham Reynolds - author and specialist on Constable's work."

'Dedham Vale' is due to go under the hammer at Sotheby's on New Bond Street on 24 November, with an estimate of �80,000 - �120,000.