Danish Prime Minister Mette Frederiksen told The Associated Press “you cannot spy against an ally” after reports that the United States has stepped up intelligence gathering on Greenland, a semi-autonomous Danish territory coveted by U.

Officials summoned the American ambassador to express its displeasure after the Trump Administration was said be ratcheting up surveillance.

Danish Foreign Minister Lars Lokke Rasmussen said on Wednesday he would call in the acting U.S. ambassador to Denmark for talks after the Wall Street Journal reported Washington had ordered U.S. intelligence agencies to step up spying on Greenland.