The denial came hours after the Wall Street Journal newspaper reported that the U.S. had conducted surveillance on some of its NATO allies, including Turkish authorities.
U.S. State Department spokesman Mark Toner held a press briefing on Dec. 29 in which he addressed media claims that Turkey and President Erdoğan were currently being monitored for leads into “radical groups in Syria.”
“In terms of your specific allegations about President Erdoğan, I've never heard of such allegations. I won't speak to beyond that what our intelligence activities may be” Toner stated.
In addition to being a member of a coalition fighting to destroy the Islamic State (IS), Turkey is a valued NATO ally, according to Toner.
“We value their input, their participation in the anti-IS coalition, and we have, again, a very close relationship with them. We share information with them, so there's no reason to believe that we would ever conduct ourselves in that way” Toner said.
He said the U.S. changed its approach to surveillance after former National Security Agency (NSA) contractor Edward Snowden exposed much of the agency's spying operations in 2013.
In its reporting, WSJ alleged that the Obama administration put certain allied leaders on a so-called protected list, shielding them from NSA snooping but excluded other allies, including Turkish President Recep Tayyip Erdoğan and Israel Prime Minister Benjamin Netanyahu.
White House National Security Council spokesman Ned Price said President Barack Obama has instructed his administration to refrain from monitoring communications of allied foreign leaders.
In 2013, Snowden leaked information that showed the NSA had tapped the phone calls of German chancellor Angela Merkel and her closest advisers and staff for years
The revelation strained ties between Germany and the U.S.
The WSJ also reported that the NSA's foreign eavesdropping included phone conversations between top Israeli officials, U.S. lawmakers and American-Jewish groups.
White House officials believed the intercepted information could be valuable to counter Netanyahu's campaign against the nuclear deal with Iran, according to unnamed officials, the WSJ alleged.
NSA eavesdropping revealed to the White House how Netanyahu and his advisers had leaked details of the U.S.-Iran negotiations, which they learned through Israeli spying operations, the newspaper reported.
The NSA reports allowed officials from the Obama administration to scrutinize Israeli efforts to turn congress against the deal, according to the WSJ.