North Korea says it has carried out a "very important test" at a satellite-launching site. The KCNA state news agency said the results would be used to upgrade the country's strategic status. It provided no further details. Analysts believe it could be a ground-based test of an engine to power a satellite launcher or an intercontinental ballistic missile. It comes after Pyongyang appeared to shut the door on further US talks. "We do not need to have lengthy talks with the US now, and denuclearisation is already gone out of the negotiating table," the North Korean envoy to the UN, Kim Song, said in a statement on Saturday.