Seven key countries at the United Nations have agreed new sanctions against North Korea, as punishment for its recent nuclear and rocket tests.The draft resolution will go to a Security Council vote on Friday. It is described by America as “very strong, credible and appropriate.” Pyongyang’s nuclear weapons test last month, and a series of long- and short-range missile launches, have raised tensions on the Korean peninsula. Washington has reaffirmed its commitment to protect the south in case of attack. Part of the UN draft calls for, but does not require, states to inspect suspicious ships carrying North Korean cargoes. Pyongyang has said any search would be treated as an act of war.