North Korean media are calling for increased loyalty to leader Kim Jong Un ahead of the 90th anniversary of the founding of the country's military.

On Thursday, the ruling Workers' Party newspaper, Rodong Sinmun, featured a long article on the Korean People's Revolutionary Army, which was founded on April 25, 1932.

The article praised the late Kim Il Sung, the current leader's grandfather and founder of the army that was the predecessor of the current Korean People's Army.

It said the maneuvers of the hostile forces targeting the heart of the revolution are increasing by the day.

It calls on the country's people to make their unity one thousand times stronger and to overcome every challenge head-on.

Also on Thursday, the website of North Korea's committee for peaceful reunification carried a statement that again slammed the US-South Korea joint military drills that began on Monday.

The statement also refers to the joint drill by Japan's Maritime Self-Defense Force and a carrier strike group of the US Navy led by a nuclear-powered aircraft carrier that was held earlier this month in the Sea of Japan.

The statement said the situation on the Korean Peninsula is at its worst state.

Speculation is growing that North Korea will stage a major military parade by its regular army in a square in central Pyongyang on or around the military's anniversary next Monday and showcase its latest weapons.