U.S. and Danish officials lobbied the developer of Greenland's largest rare earths deposit last year not to sell its project to Chinese-linked firms, its CEO said, adding it has been in regular talks with Washington as it reviews funding options to develop the island's critical minerals.

The move underscores the long-running economic interest U.S. officials have had in the Danish territory, well before U.S. President-elect said.

Rare earths have strong magnetic properties that make them critical to high-tech industries ranging from electric vehicles to missile systems. Their necessity has given rise to intense competition between Chinese and Western interests to ease China's near-total control of their extraction and processing.
Greg Barnes, CEO of privately held Tanbreez Mining, said U.S. officials who visited the project in southern Greenland twice last year had repeatedly shared a message with the cash-strapped company: do not sell the large deposit to a Beijing-linked buyer.