The U.N. Children's Fund (UNICEF) and the Red Cross have resumed the delivery of food to Khmer Rouge areas along the disputed border between Thailand and Cambodia.

After a break of six weeks, food deliveries began again last Monday when 1,200 women each received two ration packs of rice and fish at the Khmer Rouge camps of Tapprik and Nong Pru, south of Aranyaprathet.

Today Charles Egger, the deputy executive director of UNICEF, said that the authorities in Phnom Penh and Hanoi have been informed of the distribution. They had protested that the food supplies have built up the strength of the Khmer guerrillas.

"They were not pleased," Egger said, when asked for their reaction.

Vietnamese forces crossed the Thai border from Cambodia June 24 and occupied two large Cambodian refugee camps and two Thai villages. A food station run by relief agencies outside the Thai village of Nong Chan was one of the camps overrun. The Vietnamese attack also halted the "human land bridge," the huge traffic of oxcarts and refugees from Thailand to Cambodia, which had carried much of the food and relief aid into Cambodia.

The annoucement came just over a month after Egger and his Red Cross counterpart, Jean-Pierre Hocke, decided to terminate all aid to the camps as of July 17, because of the impossibility of ensuring that it would not reach guerrillas.

Officials say the about-face has been caused by the unwillingness of any other organization to take up the burden of feeding the camps and also intense pressure from the Thais, who have always feared that the Khmer Rouge would attack food convoys inside Thailand and cause further tension along the border if their food was cut off.

There remains, however, the problem of ensuring that the food is not handed over to the guerrillas by women once it is inside Cambodia. Egger said that officials have already crossed the border to try and monitor the food, even though the agencies have always been alarmed about the dangers, particularly after a Red Cross official and two photographers were recently kidnaped by Vietnamese.

The question is whether this rationale will satisfy the Vietnamese particularly at a time when the relief agencies are in a race against time to persuade their donors that their overall relief effort for Cambodia deserves another injection of money at the next review Sept. 3.

At the same time, two important pledges made in May have not materialized. Although the Soviets promised the use of helicopters to facilitate food distribution from provicial airfields in Cambodia during the monsoon, talks were broken off in Moscow after the Soviets demanded payment and said the helicopters would not be available until November.