Norway’s premier Erna Solberg announced on Thursday that Washington had given assurances it had stopped spying on its allies in 2014, after Oslo launched a protest against the practice.

Solberg said Norway called in the U.S. ambassador after a report that the U.S. National Security Agency had used a partnership with Denmark’s foreign intelligence unit to spy on top officials, including herself.

NATO members Denmark and Norway are close allies of the United States. Denmark hosts many key landing stations for subsea internet cables to and from  the Netherlands, Sweden, Norway, Germany and Britain.

Solberg told news agency NTB: “I am glad that the Americans clearly expressed that they changed their practice in 2014 when it comes to the surveillance of allies and that they would cooperate with us and others to understand what happened.”

Defense minister Frank Bakke-Jensen wrote on Twitter that his ministry had had a meeting with the U.S. embassy in Oslo “where we made it clear that spying on allies is unacceptable and unnecessary”.

There was no immediate comment from the U.S. embassy.

Solberg said she had also spoken with her Danish counterpart, Mette Frederiksen, about the case on Thursday.

“I reiterated to her that we consider spying on close friends and allies as unacceptable and unnecessary,” she said.