North Korea has reportedly ordered its diplomats to stay near their embassies to await “an important message”, setting off renewed speculation about the health of its leader, Kim Jong-il.

Foreign governments believe Kim suffered a stroke in August and was treated by Chinese doctors.

In Seoul, officials said last night the South Korean government was checking the report but its security agencies had detected no unusual activity across the border.

The message was reported by the authoritative Yomiuri Shimbun newspaper in Tokyo yesterday. “North Korea issued an order to its embassies . . . that their staff must refrain from making business trips so that they can be ready for an important announcement from the homeland,” the paper said.

The order, sent out in the past few days, was confirmed by “multiple sources”, it said.

The Yomiuri Shimbun has top level defence contacts in Japan and this would not be the first time that secret eavesdropping information had been leaked. However, it said experts were divided over what the message meant.

While world attention is focused on the health of the reclusive dictator, there has been a sharp increase in tension between North and South Korea.

Late last week North Korea issued a threat to sever all contacts with the South over its “hostile policy”. Its state-controlled media has unleasheda virulent tide of abuse against Lee Myung-bak, the conservative president of South Korea.

“If this group of traitors keep to the road of reckless confrontation with the DPRK [North Korea] . . . this will compel it to make a crucial decision including the total freeze of North-South relations,” the ruling party newspaper declared on Thursday.

It appears likely that the North Korean diplomatic message was intercepted during this period and it may therefore relate to the “crucial decision” mentioned.

As for Kim, national radio reported on Friday that he had delivered supplies to a fruit farm. The North Korean leader has just achieved a political victory in seeing his country removed from America’s list of “terrorist” nations after it threatened to resume its nuclear programme.

Additional reporting: Shota Ushio in Tokyo

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