The United States and the Republic of Korea will stage their second joint military exercise on Monday, provoking the Democratic People's Republic of Korea's threat of "severest punishment".

The jointly military exercise will be "one of the largest joint staff directed theatre exercises in the world," said General Walter Sharp, who heads some 28,500 US troops based in the ROK, according AFP.

Responding to the US-ROK new maneuver, DPRK's military threatened on Sunday to launch the "severest punishment" against the ROK for staging the joint exercise, AFP reported.

"The military counteraction (of ROK) will be the severest punishment no one has ever met in the world," said a spokesman for DPRK's army General Staff in a statement published by state media.

About 30,000 US soldiers will take part in the exercise, a US military spokesman said, adding an unspecified number of American soldiers based in the United States would join in via computer networks.

Some 56,000 ROK soldiers will be mobilized for the drill.

The 10-day joint exercise called Ulchi Freedom Guardian is designed to prepare forces to respond "to any potential provocations," US military newspaper the Stars and Stripes said.

The newspaper also said the United Nations Command alerted DPRK military officials about this month's exercise at a meeting at the Demilitarized Zone in July.

The DPRK denounced the upcoming exercise as the "largest-scale exercise for nuclear warfare," suggesting that in retaliation Pyongyang may carry out a third nuclear test, fire artillery rounds or test-fire rockets, according to Japan's Kyoto News Agency.

China issued a warning last week that a US decision to use a nuclear-powered aircraft carrier in joint drills with the ROK in the Yellow Sea constitutes a "fresh provocation" to China and its surrounding region.

Earlier this month, Pentagon spokesman Geoff Morrell told reporters that "the USS George Washington will exercise in the Yellow Sea, in the West Sea" without specifying a date.

The Yellow Sea, which Seoul calls the West Sea, is located between the Chinese mainland and the Korean Peninsula.

Chinese Rear Admiral Yang Yi said in a recent commentary that the Yellow Sea joint exercise with the presence of the US nuclear-power aircraft carrier USS George Washington "essentially sends an unspoken message to the outside world that the US is capable of doing whatever it wants in the region and will certainly do it".

It is "a fresh provocation" to China and its surrounding region, said Yang, warning that Washington contravenes the consensus between the two countries on an "all-round, active and constructive" partnership with its show of military strength by mobilizing a fleet comprising a nuclear-fuelled aircraft carrier and other warships close to China's maritime border.

Although it will not be the first time that a US aircraft carrier coming into the Yellow Sea, China reacted with intensified protests this time due to rising Korea Peninsula tensions and US' recent claim of "national interest" on the South China Sea.

The USS George Washington has cruised along waters surrounding China after it left its base in Japan on June 14. It has covered nearly 2,000 nautical miles in East Asia during the past two months, including the participation of US-Vietnam joint exercise on Aug 11.

The ROK President Lee Myung-bak on Sunday urged the DPRK to end its military provocations and make a "courageous change" as he laid out a long-term plan for reunification.

Tensions on the Korea Peninsula have been high since late May when Seoul accused Pyongyang for torpedoing a ROK warship, which Pyongyang has denied.

The US and the ROK last month staged their first joint military drill this year targeting Pyongyang, and announced to "present a joint military exercise every month until the end of the year."

Last Monday, the DPRK military fired about 110 artillery rounds toward its own territorial waters in the Yellow Sea, a move to coincide with the last day of a naval exercise the ROK conducted close to the maritime border with the DPRK.

Professor Qiu Hao with PLA National Defense University downplayed the aircraft carrier's presence in the Yellow Sea, as one of its kind dated back 1950s and 1960s.

"(At that time) the US dare not do harm to us, not to mention China is not what it used to be anymore," Qiu said.

He said the coming of the USS George Washington is "rather symbolic in meaning than exerting substantial effects", which actually aims to maintain the US prestige and test China's reactions.

China cut off military exchanges with the US after it announced a $6.4 billion arms sale to Taiwan early this year and turned down US Defense Minister Robert Gates' offer to visit in June.