The U.S. National Security Agency (NSA) has used a partnership with Denmark's foreign intelligence unit to spy on senior officials of neighboring countries, including German Chancellor Angela Merkel, according to Danish state broadcaster DR. DR also reported that other high-level officials had been surveilled from France, Norway and Sweden, though did not name them.
The US spying, if confirmed, was going on during and after the 2013 Snowden affair, which erupted when former NSA contractor Edward Snowden revealed thousands of classified documents exposing the vast US surveillance put in place after the September 11, 2001 attacks.
Germany is a close ally of the US.
"I'm not angry, I'm stunned", said Mr Steinbrück, the former German finance minister and opposition leader who learned for the first time that he had been a target for American spying.
The NSA is said to have accessed text messages and the phone conversations of a number of prominent individuals by tapping into Danish internet cables in co-operation with the FE.
The alleged set-up, said in the report to have been codenamed "Operation Dunhammer", allowed the NSA to obtain data using the telephone numbers of politicians as search parameters, according to DR.
What reaction has there been?
DR spoke to nine unnamed sources close to the FE investigation, Reuters said.
Mrs Merkel declared that "spying among friends" was unacceptable and said later that she stood by that comment.
"Politically I view this as a scandal", Mr Steinbrück told German media.
Other European politicians have condemned the reports.
In August, Bramsen relieved the head of the country's foreign intelligence service, among others, after an independent watchdog heavily criticized the spy agency for deliberately withholding information and violating Danish laws. Norwegian Defence Minister Frank Bakke-Jensen told broadcaster NRK that he took the allegations seriously.
Media reports alleging that the USA spied on top politicians in Europe with the help of Danish intelligence are "extremely serious" if proven, the French government said on Monday.
"There should be an explicit requirement for full public disclosure not only from Denmark, but their senior partner as well", he tweeted.
Danish legislator Karsten Hoenge, of the left-leaning Socialist People's Party that is supporting Denmark's Social Democratic government, said he would quiz the Scandinavian country's defence and justice ministers in parliament about the case.
"This is not something that should be played down", Beaune said, while acknowledging that similar allegations had emerged back in 2013 that the United States had spied on Merkel.
Mr Snowden found refuge in Russian Federation.
"We discussed these things.in relation to the NSA".