Bangkok, Thailand — While the dry season fighting in Kampuchea is lighter than usual, there is a lively battle on the diplomatic front. The diplomatic battle is being waged by supporters of the anti-Vietnamese coalition organized to resist Vietnam's occupation of Kampuchea.
The diplomatic maneuvering has been heightened as Southeast Asian countries prepare for the meeting of nonaligned states scheduled for early March in New Delhi.
The political skirmishing is focused on the titular head of the anti-Vietnamese coalition government, Prince Norodom Sihanouk. The loose coalition consists of the communist Khmer Rouge (including unofficial leader Pol Pot), the anti-communist forces of Son Sann, and a group of Sihanouk loyalists.
In December the Prince began to hint broadly that he might leave the coalition. The Chinese had not accorded him the honors due a head of state when he visited Peking in November; and they had given his Khmer Rouge vice-president too many honors. Neither the Association of Southeast Asian Nations (ASEAN) nor the Chinese were giving his faction enough aid, Sihanouk complained. And he said he had just received fresh details of the murder of more than 20 relatives during Pol Pot's rule.
The most recent of many Sihanouk messages says the Prince might take five or six months sick leave. This would mean that he would be unable to address the nonaligned summit, which opens in New Delhi on March 7.
ASEAN, which consists of Thailand, Indonesia, Malaysia, Singapore, and the Philippines, had hoped that a Sihanouk speech would build on his success at the United Nations General Assembly and strengthen the coalition's standing among the nonaligned nations.
ASEAN and its allies seem to have moved quickly to attempt to mollify the Prince. Sources close to the Chinese hint that military aid to Sihanouk was under consideration both by Peking and ASEAN.
The Vietnamese would be relieved if Sihanouk did not go to New Delhi. They have strongly opposed an invitation to the Prince, and may have been helping to increase the Prince's anger. The details of the Khmer Rouge killing of Sihanouk's relatives were allegedly conveyed to Sihanouk by a French academic with close Vietnamese ties.
Despite reports of indirect contacts between the Vietnamese and representatives of Sihanouk, Hanoi is probably happy to have Sihanouk remain where he is: inside the coalition but rocking it for all he's worth.
On the military side, Vietnam so far has waged only a lightweight dry-season offensive. An important battle ended Sunday when Vietnamese troops dislodged guerrillas of Son Sann's Khmer People's National Liberation Front (KPNLF) from the base they had occupied for three weeks.
The base at Yeang Dangkum, a remote border village inside Kampuchea, was often described as ''strategic'' in press accounts of the fighting. Some observers suggest, slightly wryly, that ''historic'' would have been a better term: Yeang Dangkum was the only established settlement in Kampuchea that the anti-Vietnamese forces had controlled since 1979.
Some observers suggest that the KPNLF attacked Yeang Dangkum earlier this month because Vietnamese mortars there could easily hit the Nong Chan refugee camp, controlled by the KPNLF and housing about 35,000 to 40,000 Khmers. But to do this, the Son Sann forces committed by some estimates 2,000 of their total 9, 000 to 12,000 men; there are several other Vietnamese bases whose guns can hit the camp. The base is now back in Vietnamese hands.
A more likely reason for the attack was to prove that the KPNLF has the will to fight - something that backers of the anti-Vietnamese coalition government have voiced doubts about recently.
Despite repeated predictions in Bangkok on an imminent Vietnamese offensive, Hanoi has professed to see little use of one. ''You don't need a big net for little fish,'' Vietnamese Foreign Minister Nguyen Co Thach remarked recently.
Sources close to Hanoi say they have mainly been involved in small-scale operations, mainly using five- to six-man squads. There has been some larger-scale fighting, though. The Vietnamese are quietly telling their allies that two months ago they repeated a successful maneuver first performed early last year. They sent their troops from northeastern Kampuchea into Laos, across the Mekong River and then down into northwestern Kampuchea, hitting a large Khmer Rouge concentration from behind. The Vietnamese claim to have inflicted 300 casualities; the Chinese say that the Vietnamese tried the move but failed.