Court blocks sale of Lichtenstein work that was reported stolen 40 years ago

Lichtenstein's 'Electric Cord', bought in 1970 for £750 and now said to be worth £4m

A painting by the prominent pop artist Roy Lichtenstein has been discovered more than four decades after it went missing, and has sparked a legal battle to make sure the work, worth £4m, does not disappear again.

The black-and-white Electric Cord, bought by the Leo Castelli Gallery in New York in 1970 for £750, disappeared after it was sent out to be cleaned.

When it failed to return, Mr Castelli, the gallery owner who had given Lichtenstein his first solo show in 1962, reported it stolen. His widow, Barbara Castelli, reported the theft again in 2006. The work resurfaced last month in a warehouse on New York's Upper East Side.

The Roy Lichtenstein Foundation alerted Mrs Castelli to the find after it was called in to authenticate the painting, which according to court records had been shipped in from Colombia in an attempt to sell it.

The Manhattan Supreme Court agreed on Tuesday to block the sale temporarily after an application by Mrs Castelli's lawyers, who said: "We're concerned that this painting is just going to disappear."