Dhaka, April 5 -- Denmark's Prime Minister Mette Frederiksen has called for increased Arctic defence collaboration with the United States during a visit to Greenland, and firmly dismissed Washington's desire to annex the semi-autonomous Danish territory.Frederiksen's visit follows months of tension between Washington and Copenhagen over US President Donald Trump's repeated declarations that the Arctic island should become a part of the US.At a news conference with the outgoing and incoming Greenlandic prime ministers on Thursday, Frederiksen switched to English to address the US directly, inviting it to strengthen security in the Arctic together with Denmark and Greenland."I would like to take this opportunity to send a message directly t...