Has the Denmark strait ever frozen completely?

The Denmark Strait, which separates Iceland and Greenland, has never been completely frozen. However, the strait has seen significant ice coverage during the coldest periods of the year, particularly during the winter months of January and February. Icebergs and sea ice regularly drift through the strait, and in extreme conditions, the formation of pack ice can make navigation challenging. Despite these occurrences, the Denmark Strait has remained navigable throughout history.