BERLIN (Reuters) - German Chancellor Angela Merkel and Chinese President Xi Jinping agreed in a telephone call on Thursday about the need to tighten sanctions against North Korea in light of Pyongyang s latest nuclear weapons test, a spokesman for Merkel said. Both leaders expressed deep concern about the current situation in North Korea, and viewed the latest North Korean nuclear weapons test as a significant danger for the security of the entire region, as well as a violation of international law, Steffen Seibert said in a statement.  Both leaders said they supported a tightening of the sanctions against North Korea,  he said.  At the same time, however, it was important to continue seeking dialogue to peacefully resolve the current tensions, he added. 