The veteran ships have not been in continuous use over the last 16 years, but have been well-maintained, the state said.

The vessels are the 2,200-gt Thorbjorn (built 1980) and the 3,000-gt Danbjorn (built 1965) and Isbjorn (built 1966).

Denmark is not expecting a domestic Danish company to buy them.

"I have no idea who might sign up as a buyer, and what the price will be. Maybe they can work in the Gulf of Bothnia or equally cold waters”, said Social Democratic Party defense spokesman Bjarne Laustsen.

The icebreakers are based in Frederikshavn, with crews of four men maintaining them year-round.