NATO Secretary General Jens Stoltenberg (L) and Romanian President Klaus Iohannis attend a news conference in Bucharest, Romania, Jan. 31, 2019. NATO stays the bedrock of the European security and the efforts of European Union (EU) for defence are complementary to and not competing with NATO's, the Alliance's Secretary General Jens Stoltenberg said here Thursday. (Xinhua/Cristian Cristel)