Merkel complained to President Barack Obama on Wednesday after receiving information her phone may have been monitored. German spy chiefs plan to travel to Washington for talks.
Interior Minister Hans-Peter Friedrich was quoted Sunday as telling newspaper Bild am Sonntag he wants "complete information on all accusations" and that "if the Americans intercepted cellphones in Germany, they broke German law on German soil." He added wiretapping is a crime and "those responsible must be held accountable."
News magazine Der Spiegel, whose research prompted the government's response, reported that a document apparently from an NSA database indicates Merkel's cellphone was first listed as a target in 2002.