Germany's foreign intelligence agency recorded at least one phone conversation held by US Secretary of State John Kerry, a German magazine said on Saturday, potentially embarrassing Berlin which previously reprimanded Washington for its surveillance.
Der Spiegel cited unnamed sources as saying security agents at Germany's BND had intercepted Kerry's words when he was in the Middle East negotiating between Israelis, Palestinians and Arab states last year.
In Washington, USState Department spokeswoman Laura Seal said in an e-mail concerning the Spiegel report: "We decline to comment."
The recording of at least one of Kerry's phone calls seemed to have been immediately deleted, the magazine said in a pre-publication copy of an article. It did not give any evidence for this.
On Friday, German media reported that German security agents tapped a conversation involving Kerry's predecessor, Hillary Clinton, while she was Secretary of State and had not immediately deleted the recording.
Spiegel said that phone call had taken place in 2012 between Clinton and former UN chief Kofi Annan, who had just returned from negotiations in Syria and wanted to brief Clinton.
Both Germany's government and a spokeswoman for the National Security Council at the White House declined on Friday to comment on the reports.
The magazine cited unnamed security sources as saying several US officials had been intercepted by the BND when making phone calls via satellite in a plane but that these interceptions had been unintentional "bycatch".
A BND spokeswoman told Reuters Germany was not tapping the phones of allied countries and said the United States was not a target.
"Any accidental recordings are deleted immediately," she added.
A spokesman for the German government said it was up to the parliamentary control committee to deal with the accusations.
Bild newspaper cited a US secret service employee as saying the phone calls of the secretary of state were encrypted just like those of the president so it would be "impressive if the BND was able to crack this encryption" and it was more likely Clinton's statements were intercepted on an unsecured line.
Relations between the United States and Germany were hit last year by revelations by former US National Security Agency (NSA) contractor Edward Snowden that Washington spied on German officials and bugged the phone of Chancellor Angela Merkel.
The dispute was revived in July when Germany's Federal Prosecutor arrested Markus R., a 31-year old employee of Germany's foreign intelligence agency (BND), on suspicion of spying for the Americans.
German media said on Friday they had discovered documents showing the German government had ordered the BND to spy on a NATO partner state, without naming the country. On Saturday Der Spiegel said Turkey was and still is the target.
Merkel said in an interview last month that the United States and Germany had fundamentally different conceptions of the role of the intelligence service, and she stressed the Cold War was over.