China has warned that conflict could break out "at any moment" over North Korea amid fears it is preparing to launch a sixth nuclear test “at any time” or more missiles in defiance of UN sanctions and stark warnings from the US. China's Foreign Minister Wang Yi said it was necessary to prevent the situation on the Korean peninsula from going down "an irreversible route". The US has sent an aircraft carrier to waters off the peninsula and is conducting its biggest-ever joint military exercises with South Korea.  China reportedly deployed up to 150,00 troops on its North Korean border,