"I do not see that he [N. Korean leader Kim Jong-il] will give up his nuclear capability," Gen. Walter Sharp told U.S. lawmakers on Tuesday during hearings on Pentagon's budget for 2012 fiscal year.

"I think it is clear that Kim Jong-il believes he has to have it for regime survival," Sharp said adding that the U.S. military should maintain a strong presence on the Korean peninsula to stave off any threats to stability in the region.

The United States has kept a large military contingent in South Korea since the Korean War ended in an uneasy truce in 1953, and about 37,000 troops are currently stationed there.

North Korea is banned from conducting nuclear or ballistic missile tests under UN Resolution 1718, adopted after Pyongyang's first nuclear test on October 9, 2006.

However, the country carried out a second nuclear test on May 25, 2009, followed by a series of short-range missile launches, and has threatened to build up its nuclear arsenal to counter what it calls hostile U.S. policies.

The six-party talks on Pyongyang's nuclear ambitions involving the two Koreas, China, the United States, Russia and Japan came to a halt in April 2009 when North Korea walked out of negotiations to protest the United Nations' condemnation of its missile test.