NATO remains of central importance to Germany's defense despite tensions within the alliance, German Chancellor Angela Merkel said on Thursday. US President Donald Trump in May singled out Germany as a member of North Atlantic Treaty Organization that was not doing enough to contribute fully to the organization. “It is no secret that the transatlantic alliance is under strain at the moment but we are convinced that the alliance remains central to our common security,” Merkel said in a speech to parliament. She also warned that Europe must keep talking to the US to avoid a trade war, Reuters reports.