According to Danish military regulations, the country will fire first if the United States (US) decides to attack Greenland.
The plan was taken in the wake of President Donald Trump and his top advisers' plans to buy Greenland and take over the island's defense assets.
Tensions have been rising this week following the Trump administration's threat to mobilize US troops to take over the island.
The threat from Washington has continued to increase despite European leaders, including Sir Keir Starmer, warning that they will not stop to defend Greenland.
The Danish Ministry of Defense yesterday confirmed the existence of a 1952 regulation that requires its armed forces to attack any invading force immediately without waiting for orders from central authorities.
The confirmation came after Danish newspaper Berlingske questioned the status of the regulation.
According to a report by Berlingske, the regulation stipulates that in the event of an invasion, the attacked force must immediately begin fighting without waiting for orders, even if commanders have not yet received any official declaration of war.
However, Trump insisted that the US goal in seizing Greenland from Denmark was to protect the NATO alliance from threats from China and Russia in the Arctic.
European allies are currently holding crucial talks to discuss immediate action if the US does indeed launch an attack.
