While few details of the exact work at Pituffik have been made public, the improvements come during a time of intense focus on Greenland.

The islands, which Britain has agreed to hand over to Mauritius, are home to a strategically important U.S.-British military base.

The Pentagon says the $1.5 billion potential sale "would not alter the regional military balance."

US officials say it is a "precautionary measure" and comes as Donald Trump weighs up whether to take action against Iran.

Personnel stationed at a U.S. military base in Qatar targeted by Iran last summer were advised to leave by Wednesday evening as a precautionary measure amid escalating tensions in the region, according to a U.

Forgotten military facilities are now being revived amid Trump’s new military push following the capture of Venezuelan leader Nicolás Maduro.

The U.S. has ordered some of its military personnel to depart from bases in the Middle East on Tuesday as tensions with Iran escalate.

Some personnel at the United States’ largest military base in the Middle East have been urged to leave, a US official told CNN on Wednesday, as regional nations press the Trump administration to reconsider taking military action against Iran.

U.S. personnel at a military base in Qatar have been advised to evacuate the facility amid escalating tensions with nearby Iran.