Tony Abbott and Kevin Rudd say North Korea's war threats serious Kevin Rudd said North Korea's statements were like from a re-run of a bad 1930s movie. KEVIN Rudd says the commentary coming out of North Korea is like a re-run of a bad 1930s movie but that threats of nuclear warfare need to be taken seriously. As Pyongyang this morning said it had given final approval for a nuclear attack on the United States, Mr Rudd said China did not do itself any favours by retaining ties with the rouge state. The former prime minister, who is on a speaking tour of the US on China relations, said the "appalling set of statements" from North Korea of late were "like a re-run of a bad 1930s movie." "They have nothing to do with the language of 21st century diplomacy by any nation state anywhere in the world today," Mr Rudd told students at Harvard University. He said China didn't need enemies "with friends like North Korea." Tony Abbott today said North Korea was the "ultimate rogue state" and urged Julia Gillard to push China to act to calm the tensions in Pyongyang when she visited later this week. "It is important the international community does what it can to hold back North Korea," the Opposition Leader said. Mr Abbott's foreign affairs spokeswoman Julie Bishop told News Limited she would be visiting China for the BOAO trade forum this weekend and would raise the issue of North Korea with senior government officials. "The threats from North Korea have become increasingly dire in recent weeks and must be taken seriously," Ms Bishop said this morning. The United States is sending its new, ultra-advanced THAAD missile defence system to Guam. Here's how it works. Ms Bishop said this particular escalation was worrying because South Korea had said it would retaliate to any northern attack, whereas in the past it had shown restraint. "The potential for escalation is obvious," she said. Ms Bishop called on Foreign Minister to make clear exactly what Australia would do to limit North Korea's activities. "Senator Carr should clarify what he has in mind ... there is currently no two way trade between North Korea and Australia so I'm not quite sure how further sanctions directly from Australia could be imposed," she said. Kim Jong-un should be leading his nation on a path to peace, this is not in the interests of the North Korean people.