US must recognise it as 'nuclear weapons state': N Korea

North Korea demanded Sunday that the United States recognises it as a "legitimate nuclear weapons state" following its fifth and largest atomic test.

"(President Barack) Obama is trying hard to deny the DPRK's (North Korea's) strategic position as a legitimate nuclear weapons state but it is as foolish an act as trying to eclipse the sun with a palm," said a foreign ministry spokesman quoted by the official KNCA news agency.

The spokesman in a statement defended the test, which has been slammed worldwide, as a necessary response to what he termed a US nuclear threat.

The North would work to increase its nuclear force "in quality and in quantity", the statement said.