Relations between the United States and Germany continue to deteriorate. The discovery of a second spy within the German government has caused German politicians to demand answers from the U.S. government and has also led to the expulsion of the U.S intelligence chief in the nation.

Last year it was revealed that the National Security Agency (NSA) was tapping the cell phone conversations of various German politicians, including the German Chancellor Angela Merkel, according to Der Spiegel. The magazine reported that the NSA used the roof of the U.S. Embassy in Berlin as the site from where calls where intercepted.

Germany began an investigation into the matter in June of this year to uncover the extent of American intrusion in German affairs. According to The Associated Press, the investigation planned to discover who was involved in the spying of German politicians and institutions, both foreign nations and operatives in Germany.

The subsequent inquest has led to the discovery of two spies working for the U.S. government within the German government. The first one was uncovered last week when a 31-year-old man was arrested under suspicion of being a double agent working for Washington, according to the New York Daily News. The spy exchanged information on the NSA probe as well as other documents with the U.S. in exchange of $50,000.

However, as Berlin reels over the news of its ally spying on its government, they discovered a second spy within its midst. Reuters reported that the second spy was uncovered on Wednesday and had been working within the Ministry of Defense. Conflicting reports say that he either worked for the Ministry of Defense or worked for the Foreign Affairs Ministry and was on assignment at the Defense Ministry.

Germany's Defense Minister Ursula von der Leyen told the Berliner Zeitung newspaper, "It is not yet clear what is behind this." She later said that the NSA scandal had "shaken confidence" in the U.S., adding that "not everything that is possible is politically acceptable".

According to the German site The Local, following the news of the second spy, the German government has expelled the United State's spy chief in Berlin.

"The representative of the U.S. intelligence services at the Embassy of the United States of America was asked to leave Germany," German government spokesman Steffen Seibert said, adding that the request comes after months of unanswered questions asked by Germany to the U.S.

"The Government takes these acts very seriously. It remains essential for Germany, in the interest of the security of its citizens and its forces abroad, to work closely on a basis of trust with Western partners, especially the United States," he said.

"But for that to happen, mutual trust and openness are necessary."