AMONG THE INTERNATIONAL agencies sending food to Cambodia, as within the United States government, a pained argument has arisen over Phnom Penh's refusal to distribute food already on hand to people who are starving. Should the senders swallow hard, accept Phnom Penh's and Hanoi's and Moscow's claim of temporary logistical difficulties, and keep shipping in more food? Or should the senders halt further shipments and raise a ruckus, telling the world the plain truth that there is a conspiracy afoot to withhold available food in order to force the senders to recognize the Phnom Penh regime, as well as to starve out the Cambodian opposition?

It is incredible that any regime would be so cruel and cynical as to force this sort of choice on goodwilled people whose dominant aim is merely to reduce a ghastly toll to death and suffering. The Heng Samrin regime in Phnom Penh, its patrons in Hanoi and its patrons in Moscow have won deep and permanent obloquy for their sponsorship of starvation in Cambodia. But for the international relief agencies and concerned governments to join this conspiracy would be unthinkable, and they would be doing precisely that if they were meekly to sit by, mumbling excuses and keeping on adding to the stockpiles of undistributed food in Phnom Penh.

The international agencies know whether food is leaving the warehouses for the countryside. From this minute on, they should insist that the stores be distributed before they are replaced. This must be done even though there is no good way to ensure that hunger and need will be the sole criteria for distribution. It is absurd even to entertain the thought that those who have been committing atrocities in Cambodia -- Heng Samrin, Vietnam, the Soviet Union, in their respective fashions -- should be treated with the discretion and respect accorded civic-minded people. They should be isolated in international opinion and held accountable for their violation of civilized norms. They cannot be allowed to get away with murder.