S. Korea asks U.S. if leader was wiretapped by U.S. spy agency

South Korea has asked the United States to clarify whether its president was among the leaders of 35 countries who were reportedly wiretapped by the U.S. National Security Agency, Yonhap News Agency reported Sunday, citing a government official.

"We are checking with the U.S. side for verification," the official was quoted as saying. "The government is closely following the issue and is determined to respond strictly."

The Guardian, a leading British daily, reported on Friday that the NSA monitored the phone conversations of 35 world leaders, citing a classified document from 2006 provided by whistleblower Edward Snowden, a former intelligence contractor.

In 2006, South Korea's president was Roh Moo Hyun.

The South Korean official said Seoul previously made a similar request to Washington after The Guardian, citing other NSA documents leaked by Snowden, reported last month that U.S. intelligence services eavesdropped on 38 embassies and missions in the United States, including those of allies like South Korea and Japan.

"At that time, the U.S. had said that it gravely understands the concerns of the ally and is reviewing the country's intelligence activities in general," the South Korean official told Yonhap.

Amid an international uproar, the White House has recently said it is examining other countries' concerns as part of an ongoing review of how the U.S. spy agencies gather intelligence.

In a related matter, informed sources told Kyodo News on Saturday that the NSA sounded out the Japanese government around 2011 for cooperation in wiretapping fiber-optic cables carrying phone and Internet data across the Asia-Pacific region.

The sources said Japan decided it could not do so because under current legislation.