New North Korean leader Kim Jung-un looks unlikely to depart from the nuclear brinkmanship, threats to his region and repression of his father and grandfather, the top U.S. military commander for the Asia-Pacific region said on Tuesday.

He's a Kim, and he's surrounded by an uncle and Kim Jong-il's sister and others that I think are guiding his actions, said Admiral Robert Willard, head of U.S. Pacific Command.

So in that sense, we would expect ... more of the same. The strategy has been successful through two generations, he told a U.S. Senate Armed services Committee hearing in Washington.

It wouldn't surprise us to see an effort to make the strategy work for a third.

The Hawaii-based admiral described the hereditary Kim strategy as one that embraces nuclearisation, missile development, WMD proliferation, provocations and totalitarian control over North Korean society.

Kim Jong-un, believed to be in his late twenties, is the son of former leader Kim Jong-il, who died suddenly in December having built a state with nuclear weapons capacity and presided over a famine that killed millions in the 1990s.

In the communist world's first hereditary succession, Kim Jong-il took over the impoverished country of 23 million when his father, state founder Kim Il-sung, died in 1994.

We're observing closely for signs of instability or evidence that the leadership transition is faltering, said Willard.

We believe Kim Jong-un to be tightly surrounded by (Kim Jong-il) associates, and for the time being the succession appears to be on course.

His testimony comes after North Korea threatened on Saturday to wage a sacred war in response to joint military exercises planned by South Korea and the United States. Pyongyang typically decries the annual drills with vitriol.

The sabre-rattling by North Korea followed talks with the United States last week on its nuclear program and food aid, the first under Kim Jong-un.

In another sign of diplomacy continuing, Willard said cooperation with North Korea was set to resume to recover the remains of U.S. soldiers missing since the 1950-53 Korean War.

Willard said an American ship carrying equipment for the mission had arrived at the North Korean port of Nampo, southwest of the capital Pyongyang. Recovery operations are due to start in March.

More than 7,900 U.S. soldiers are listed as missing from the Korean War, with some 5,500 estimated to be buried in the reclusive North. Joint recovery efforts were halted in May 2005 over concerns created by North Korea's nuclear programs.

(Reporting by Paul Eckert in Washington and Jeremy Laurence in Seoul; Editing by Ron Popeski)