A German political opposition leader has called for a complete halt to the ongoing European Union-United States trade negotiations, further indicating a breakdown between the two longstanding allies over spy-related issues.

"I would interrupt the negotiations until the Americans say if German government offices and European institutions are bugged or wiretapped,” Peer Steinbrück, leader of the Social Democratic (SPD) party, told German public television broadcaster ARD (Google Translate) on Sunday evening.

Steinbrück is running as a rival candidate against Chancellor Angela Merkel in the upcoming election next month. He formerly served as Minister of Finance in the Merkel government and also as the Minister President (Governor) of North Rhine-Westphalia, Germany’s largest state by population.

“We don't know if the Americans may be sitting under our desks with some technical devices,” he added.

His remarks came just after the German magazine Der Spiegel disclosed that the National Security Agency bugged and wiretapped the United Nations and 80 consulates and embassies worldwide.

"Merkel is saying one thing about all this: Let's wait,” Steinbrück noted. “I don't think a chancellor should wait when civil liberties are at stake.”

Chancellor Merkel has said that she has no evidence that the United States has violated German law, despite the fact that her government is currently negotiating a bilaterial “no-spy” agreement.

For decades, Germany has had much stricter privacy and data protection laws than the United States. American security consultant and Tor developer Jacob Appelbaum and American filmmaker (and Glenn Greenwald’s primary colleague on the Ed Snowden leaks) Laura Poitras are known to have taken up residence in Germany.