The outgoing administration of US President Joe Biden is making a last-ditch push for mining companies and others to invest in Greenland, a move aimed at cementing its critical minerals diplomacy and boosting Western supply of materials for the energy transition.

Before President-elect Donald Trump takes office in January, Biden and his staff have been taking multiple steps to shore up their legacy, including boosting aid to Ukraine and rushing to approve US mine permitting and financial incentives.

Jose Fernandez, the State Department’s under secretary for economic growth, energy and the environment, spent four days in Nuuk last week to meet with the Ministry of Foreign Affairs and Minerals Resource Authority.

Greenland, a semi-autonomous part of Denmark and host to one of the largest US Air Force bases, contains large deposits of most of the minerals considered critical by the US Geological Survey.

“That was my attempt to provide to investors a glimpse of what opportunities exist in Greenland,” Fernandez told Reuters. “Greenland wants to become the next mining frontier.”

The visit culminated in an eight-hour conference call last Wednesday from Nuuk moderated by Fernandez between Greenland officials and more than 70 Japanese, European and US mining companies and other potential investors.

Diplomats from Australia, the United Kingdom and the European Union, as well as the US Export-Import Bank and the European Investment Bank, joined the call, which focused on seven projects, including a rare earths project from Neo Performance, a nickel project from Anglo American and a molybdenum project from Greenland Resources.

"In Greenland, we see the development of critical minerals as a shared global responsibility, where our country can take on a leading role," said Naaja Nathanielsen, Greenland's minister for industry, trade, minerals, justice and gender equality.

The US State Department has been offering permitting, mapping and other regulatory advice to Nuuk officials, as well as helping to draft a mining investment law, all aimed at prodding investment in Greenland at standards considered higher than Chinese-linked rivals.

"Yes, we want to get their critical minerals and use them in our economy, but we don’t want to do that at their expense,” said Fernandez.

Trump, who takes office in January, unsuccessfully tried to buy Greenland from Denmark during his first term.

"I cannot forecast what the next administration will do, but the business case will not change," Fernandez said. "The demand for critical minerals worldwide is increasing exponentially."