She told parliament that Germany and the US are still far apart in their views on the mass surveillance of US National Security Agency (NSA), warning spying activities would lead to mistrust between allies and less rather than more security, Xinhua reported.
But Merkel spoke out against cancelling talks between the US and the European Union about a transatlantic free trade area, saying for all their differences, Germany could not wish for a better partner than the US.
Merkel: US, Germany still apart on views on surveillance
Relations between Germany and the US have been strained by revelations of US mass surveillance of online and photo data, especially the allegations about US tapping of Merkel's mobile phone.
US President Barack Obama told German TV earlier this month that he doesn't want to harm the friendly relationship with Merkel, but made clear the US intelligence agencies will not stop collecting data on government intentions of other countries.
US Secretary of State John Kerry is going to pay a visit to Germany on Friday. The NSA is likely to be on the agenda of Merkel's meeting with Kerry in Berlin.