An oil painting by an artist which sold for less than £13,000 in 1975 is expected to sell for up to £600,000 at auction.

Sir Alfred Munnings’ work The Yellow Jockey was painted during the Second World War and depicts the scene just before a race at Newmarket.

When the painting was auctioned at Sotheby’s in New York almost 40 years ago it fetched £12,941 a similar price of an average home in Suffolk and Essex at the time.

Tomorrow the picture, a 20 by 24inch oil on panel work is set to fetch between £400,000 and £600,000 in Sotheby’s London while the average British house is now worth about £240,000.

A spokesman for auctioneers Sotheby’s said: “When The Yellow Jockey was included in Munnings’ retrospective exhibition at the Royal Academy in 1956, it was stated that it was painted circa 1940. Between 1940 and 1959, Munnings included a painting of the start of a race in virtually every Royal Academy show.

“These exhibits varied in the level of their finish: some were sketches for more finished pictures. By the end of the Second World War, these race starts were the principal focus of his art.”

Sir Alfred Munnings, a miller’s son, was born at Mendham, in north Suffolk on October 8, 1878 and lived and worked at Castle House, Dedham, for forty years, from 1919 until his death on July 17, 1959.

Munnings was said to be entranced by the starts of races particularly at Newmarket.

In his book, The Finish, he wrote about seeing thousands of race starts at the course and the influence it had.

He would often watch several races a day and kept a studio next to the track.

At Bonhams in London next Wednesday two oil paintings by royal artist, former Ipswich Art Club president, Edward Seago, are expected to sell for between £55,000 and £85,000.

Before The Barge Race, Pin Mill, is set to fetch between £30,000 and £50,000, while Beach Scene On The Suffolk Coast, is tipped to sell for between £25,000 and £35,000.