No prosecutable evidence has been found that U.S. spies tapped German Chancellor Angela Merkel's cell phone, Germany's top public prosecutor said Thursday, although the investigation continues, reported Reuters.

Former National Security Agency employee Edward Snowden leaked documents claiming that the NSA conducted widespread electronic spying on top foreign officials, including on Merkel's cell phone used for party business, which led German authorities to open an investigation.

German Attorney General Harald Range launched his investigation in June, and during a televised end-of-the-year conference today, Range laid out where the investigation currently stands.

"The document presented in public as proof of an actual tapping of the mobile phone is not an authentic surveillance order by the NSA. It does not come from the NSA database," Range said.

"There is no proof at the moment which could lead to charges that Chancellor Merkel's phone connection data was collected or her calls tapped."

The newspaper that broke the story, Spiegel, reportedly invoked its right to refuse testimony, the NSA declined to comment, and neither Germany's BND foreign intelligence agency nor Snowden provided Range's office with further details, The Washington Post reported.

Range also spoke of the ongoing investigation into a German intelligence agent suspected of passing 200 documents to the Central Intelligence Agency and offering his services to Russia. Germany may pursue its first espionage indictment since World War II against a U.S. intelligence agent who they believe was working as a mole for the U.S.

The investigation will likely conclude in early 2015.

"If nothing changes fundamentally, there could be a first indictment for espionage for a U.S. intelligence service in the history of the Federal Republic," Range said.

When reports initially arose in July of a CIA mole inside Germany's spy network, it prompted Germany to ask the U.S.'s top CIA official to leave the country, marking the most vocal response from the country to date over alleged spying.