DENMARK's National Maritime Authority has closed the Great Belt strait through which ships access the high seas and the Baltic because of a mishap with a malfunctioning shipboard missile launcher, reports Aljazeera.

Danish armed forces said a technical problem arose with a Harpoon missile on board the Danish frigate HDMS Niels Juel.

An activated but faulty missile launcher on a Danish navy vessel has triggered a closure of airspace and shipping traffic in the Great Belt strait, according to the Danish military.

Denmark's armed forces said a technical problem arose with a Harpoon missile on board a frigate as it was taking part in a test while anchored at the Korsoer naval base.

Denmark's National Maritime Authority earlier warned ships not to sail through the Great Belt strait, one of the world's busiest sea lanes and the main maritime access to the Baltic Sea, due to the risk of "falling missile fragments".

"The problem occurred during a mandatory test where the missile launcher is activated and cannot be deactivated," the military said in a statement.

"Until the missile launcher is deactivated, there is a risk that the missile can fire and fly a few kilometres away," the military added.

On its website, the Danish Maritime Authority said there was a military drill taking place in the Storebaelt straight between the Danish islands of Zeeland and Funen.

The danger area is estimated to be up to seven kilometres (4.3 miles) from Korsoer at a height of one kilometre (0.62 miles) above sea level and not in the direction of the bridge and tunnel link across the Storebaelt.