LS Lowry's painting Sunday Afternoon set to fetch up to £6 million at auction

The Stretford-born artist, who died in 1976, once said the work of a densely populated industrial landscape depicted the "battle of life".

It has gone on show at Christie's London ahead of an auction on March 20.

The auction house, which sold the work to a private collector in 1967 for a "record price", said it was expected to fetch between £4m and £6m.

The artwork, which was painted in 1957, was obtained from the collection of Sir Keith Showering, who was a former chief executive of Europe's biggest drinks business, Allied Breweries.

Phillip Harley, senior director at Christie's, said the "important painting" had remained in the collection of Sir Keith and Lady Showering since 1967, which meant the sale was "a once-in-a-generation opportunity to acquire a work of this magnitude and scale".

"The composition represents the wonder the artist felt as he recorded his many observations of the evolving society around him," he said.

The Lancashire artist's Early Morning is up for between £800,000 and £1.2 million, while Street Scene With Old Church Tower from 1964 and People Standing About from 1972 both have estimates of £400,000 to £600,000.

Born Laurence Stephen Lowry in Stretford in 1887, the artist became known for his depictions of industrial life across the North of England and a series of atmospheric seascapes.

He produced more than 1,000 artworks across his lifetime.