The top American intelligence officer in Germany has been asked to leave the country in the wake of revelations about National Security Agency spying and two recent cases in which the U.S. reportedly recruited German spies.

The request was made after months of questions about the activities of U.S. intelligence agencies in Germany went unanswered, the German federal government said in a news release Thursday.

A Parliamentary committee has been established to investigate U.S. intelligence operations in Germany, the government statement noted.

On July 2, an employee of the German Bundesnachrichtendienst (BND) intelligence agency was arrested, according to news reports.

The employee was arrested under suspicion of passing on information to Russian intelligence services, and also because he allegedly received money to pass information to a U.S. contact, according to reports. The information allegedly included details about the Parliamentary investigation into U.S. spying, according to German news media reports. German authorities confirmed the arrest.

In the wake of that arrest, German authorities confirmed they also conducted raids in a second case, to investigate the possibility that an unidentified man had engaged in spying. News reports in Germany cited government sources as saying that the unidentified man worked in the Defense Ministry's political department and was suspected of passing information to American military intelligence.

"It remains essential for Germany to continue to work together with Western partners, especially with the U.S., in the interest of security of its citizens," the German government said in its release. "However, mutual trust and openness are needed in order to work together," the government said, adding that while Germany is prepared to do this it expects the same from its closest partners.

Revelations that the U.S. National Security Agency and Federal Bureau of Investigation have for years been conducting massive surveillance of American citizens, foreigners living in the country and foreign government leaders surfaced in June last year after former government contractor Edward Snowden leaked U.S. government documents to media outlets.

"The U.S. Embassy has seen the reports that Germany has asked U.S. Mission Germany's intelligence chief to leave the country," according to a statement from the embassy.

"As a standard practice, we will not comment on intelligence matters. However, our security relationship with Germany remains very important: it keeps Germans and Americans safe. It is also essential that our close cooperation with our German government partners continue in all areas," according to the statement.

The U.S. Central Intelligence Agency had no immediate comment.

Loek is Amsterdam Correspondent and covers online privacy, intellectual property, open-source and online payment issues for the IDG News Service. Follow him on Twitter at @loekessers or email tips and comments to loek_essers@idg.com