Phnom Penh's prince rattles the peace process: Raymond Whitaker, Asia Editor, assesses the effect Norodom Sihanouk's decision not to co-operate with the UN will have on an already troubled peace mission

THE Japanese head of the United Nations mission in Cambodia, Yasushi Akashi, goes to Peking on Friday for what may prove to be a last attempt to save the most ambitious and expensive peace operation in UN history from collapse. There he will meet Prince Norodom Sihanouk, who retreated to the Chinese capital in November, allegedly on medical grounds.

Earlier this week Prince Sihanouk announced that he would no longer co- operate with the UN Transitional Authority in Cambodia (Untac) or Hun Sen's government in Phnom Penh, because Untac had failed to protect members of the royalist party led by his son, Prince Norodom Ranariddh. The party is known as Funcinpec, from its French initials.

Prince Sihanouk, always described as 'mercurial' in newspaper profiles, is notorious for dramatic pronouncements that are forgotten almost as soon as they are made. 'He wants people to come to him on bended knee, assure him that he is the father of his country, and beg him to come back as the only man who can hold Cambodia together, but everyone is starting to lose patience with him,' said a diplomat from one of the five permanent UN Security Council powers that brokered the peace agreement. 'Akashi will tell him it is time he started exercising some leadership.'

A senior UN official in Phnom Penh put it more bluntly. 'If the old man really cared for the Cambodian people, maybe he would get his royal behind over here instead of throwing mud at us from Peking,' he told Reuters.

There is no doubt that Mr Akashi needs the help of the 70-year-old Prince. Despite its successes in repatriating some 230,000 refugees from Thailand and registering more than 4 million voters for the elections in May, the pounds 1.3bn Untac mission is in trouble. The Khmer Rouge, one of the four factions that signed the Paris peace accords in October 1991, has refused to disarm or allow Untac officials into the areas it controls. In response, the Phnom Penh government has held back on demobilising its forces, and is believed to be behind most of the worsening intimidation of politicians attempting to prepare for the elections.

Mr Akashi's problem is that the least popular factions are the best-armed, while those most likely to appeal to the voters, Funcinpec and, to a lesser extent, the Khmer People's National Liberation Front of a former prime minister, Son Sann, lack military muscle. Untac seems reluctant to protect political workers and human rights campaigners for fear the government will emulate its enemy, the Khmer Rouge, and pull out of the peace agreement.

Yesterday Mr Hun Sen seized upon Prince Sihanouk's discontent to repeat his view that the Khmer Rouge should be given an ultimatum to co-operate. If they did not, Untac should use its 16,000 peace-keeping troops to hunt them down as outlaws. Apart from this not being his mandate, Mr Akashi is having enough trouble keeping the Phnom Penh government at arm's length to agree to such an adventure.

Despite increasing ceasefire violations and political intimidation, not to mention corruption and crime in Phnom Penh, there is little doubt that Untac could hold a reasonably credible election in May, with or without the Khmer Rouge. The question is what would happen next. Mr Hun Sen argued yesterday that to carry on along present lines would cause the partition of Cambodia, and ultimately a return to civil war, which would be a bitter humiliation for the UN.

Diplomats say Mr Hun Sen is probably right - unless Cambodian leaders work together. 'They have wasted the 14 months since the Paris agreement,' said one diplomat. 'The UN mandate runs out at the end of July, and there will be no more money or manpower after then. They have six and a half months to get their act together.'