North Korea's top military body Monday defended its recent missile tests as a legitimate exercise in self-defence, and said South Korean and US charges of provocation were malicious and hypocritical.

The North has conducted half-a-dozen missile, rocket and heavy artillery tests over the past month, earning a verbal slap on the wrist from the UN Security Council.

The launches included a number of ballistic missile tests, which North Korea is banned from conducting under existing UN resolutions.

The National Defence Commission (NDC) said condemnation of the tests was absurd given the large-scale military drills the South Korean and US forces conduct every year south of the border.

The military allies carried out a joint naval exercise last week, and a separate two-day "search and rescue" maritime drill kicked off Monday with Japan also participating.

The response of Seoul and Washington was akin to a burglar rudely criticising the owner of the house he is trying to rob, an NDC spokesman said in a statement carried on the North's official KCNA news agency.

"The real provocations and threats made to the Korean peninsula are the whole gamut of political and military moves being pushed forward by the US," the spokesman said, citing the annual joint drills in South Korea.

"The more desperately the US and South Korean authorities resort to gangster-like hostile acts, the more deadly retaliatory actions they will face," the spokesman said, warning that any North Korean response would come "like a bolt from the blue".

Pyongyang has been playing hawk and dove in recent weeks, mixing its tests with peace gestures that have been largely dismissed by Seoul.

The two Koreas are currently trying to sort out logistics for the North's participation in the Asian Games, which begin in September in the South Korean city of Incheon.

Talks last week broke down with the North accusing the South of duplicity and arrogance, and threatening to boycott the event.

Despite the failure of the talks, North Korean state media on Sunday quoted leader Kim Jung-Un voicing "great expectations" for the North's athletes at the Asiad.