It made no mention of US President Donald Trump's repeated claims to the Danish autonomous territory.

Germany, France, Sweden and Norway on Wednesday announced the deployments, shortly after a Washington meeting between US, Danish and Greenlandic officials had failed to resolve disagreement over the island.

The German defence ministry said Wednesday that the 13-strong Bundeswehr team aimed to help "explore the framework conditions for possible military contributions to support Denmark in ensuring security in the region".

In its statement on Thursday, the ministry echoed the US position that the main regional threat is posed by Russia and China.

Defence Minister Boris Pistorius was quoted as saying: "Russia and China are increasingly using the Arctic for military purposes, thereby jeopardising the freedom of transport, communication and trade.

"NATO will not allow this and will continue to uphold the rules-based international order. It is crucial for me that we coordinate very closely within NATO, particularly with our US partners, during the joint exploration in Greenland under Danish leadership."

The ministry said the joint mission comes at the invitation of Denmark and aims "to gather fundamental information about the local conditions for operational and training opportunities".

The German unit would first fly to Denmark's Karup air base on Thursday, from where the European allies would on Friday fly together to Greenland "using a Danish civilian aircraft," said the ministry statement.

"From our perspective, this joint flight is a strong sign of our unity."