us state department deputy spokesman and mary hart said she was concerned about north korea's deliberate decision to further escalate tensions they can choose to further escalate. you can choose to come in line with the cash obligations and rejoin huge national meeting unfortunately we've seen recently particularly if the former. us defence ticket reach the cable urge north korea to discontinue such problems he said. he said she would discuss the issue with his chinese counterpart. a trip to beijing and next week chinese foreign ministry spokesman homeland expressed concern over the rising tensions on the korean peninsula and call for restraint from both sides of the small side should remain calm and not do anything to worsen tensions that you should work to protect peace and stability on the korean peninsula. the two koreas on monday afternoon exchange fighters across the disputed western sea border known as the northern limit line. tell me i had the gradient levels of threats in recent days after the united nations condemned its mid range missile launches last week and against the back