Transcript for North Korea announces new engine for nuclear missile

We go overseas for the latest on the nuclear threat from north Korea. The regime announced this weekend it is testing a new engine that could fuel a nuclear missile and that drew a sharp response from president trump on Sunday. That meeting on North Korea he's acting very, very badly. I will tell you he's acting very badly. Reporter: More from Martha Raddatz in Washington. These comments from the president come after secretary of state Rex tillerson raised the possibility of a military strike against North Korea during his trip to Asia last week. Reporter: Tillerson said the trump administration has Mott ruled out a preemptive strike against North Korea, which means they could try to take out a missile before it leaves the launchpad or disrupt a nuclear test. But despite strong words and warnings from the trump administration, or perhaps because of them, the provocations from North Korea are going ahead full steam. This latest test of that rocket engine shows significant progress towards building more powerful long-range missiles. North Korea trying to perfect a missile capable of reaching the United States with a nuclear warhead. This latest test coming just hours before secretary tillerson met with Chinese president ji and seeming to test the red line that the both have drawn. China could be a key partner in taking on the threat and appears that the Chinese leader and secretary of state tillerson found some common ground over the weekend. Yeah, as you know, George, with diplomacy what is said in public is often very different than what is said in private. The Chinese want to maintain a good relationship with north Korea and they strongly object to the kind of missile defense system that the U.S. May deploy if North Korea keeps this up, George. Okay, Martha Raddatz, thanks

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