US Defence Secretary Robert Gates yesterday warned against “provocations” from North Korea as the country’s ailing leader Kim Jong-Il prepares to hand over power to his youngest son.

Mr Gates cited speculation the succession may be accompanied by aggressive acts and said Washington remained committed to the defence of its ally, South Korea.

Speaking at a joint press conference with his South Korean counterpart, Mr Gates said “provocations will not be tolerated” but added the effect of the transition of power remained unclear.

He said all signs pointed to the eventual ascent of Kim Jong-Un in North Korea and “that’s the assumption we’re all working on, that he will in fact at some point take on that leadership role.”

Kim Jong-Un, believed aged about 27, was last week named a four-star general and given major party posts, apparently confirming his status as leader-in-waiting to his ageing and ailing father.

The current leader, now 68, suffered a stroke two years ago and also reportedly suffers kidney problems, making a transition of power more pressing.

South Korean Defence Minister Kim Tae-Young, noting the landmark party conference on September 28 that promoted Jong-Un, said that “instability” surrounding the succession could not be ruled out.

South Korea and the United States “will prepare against all possible contingencies in North Korea,” Mr Kim said through a translator.

Mr Gates said it was “a good thing at this point of transition in North Korea that our alliance is, in fact, as both the minister and I have agreed, perhaps the strongest it’s ever been.”