THE FIVE MEMBERS of the Nuclear Regulatory Commission, who hardly ever agree on anything, voted 5-0 last Friday. They concluded that two proposed exports of nuclear fuel destined for India did not meet the requirements of the Nuclear Non-Proliferation Act of 1978 and therefore could not be approved. The export licenses now go to the president, who may override the NRC. Several aspects of the NRC decision, however, should make the president rethink his announced intention of approving the exports.

The central pillar of the administration's non-proliferation policy, and of the law Congress enacted in support of it, and of the landmark Non-Proliferation Treaty, is reliance on an international system of controls and inspections known as safeguards. The NPT requires its signatories to put all of their non-military nuclear facilities under safeguards. However, many recipients of U.S. nuclear supplies have not signed the NPT. The fundamental contribution of the 1978 law was its requirement than an absolute condition of future U.S. nuclear exports would be the functional equivalent of NPT membership: full safeguards.

Congress allowed a two-year grace period so exports could continue to nations that did not meet the safeguards requirement. That period expired on March 10. However, in asking for the NRC's approval, the Department of State argued that the two Indian licenses should be considered as falling within the allowed grace period because the shipping date that India had intended fell before March 10. After extensive review of the legislative history of the law, the NRC unanimously disagreed.

Its decision puts the proposed exports in a new light, because now presidential approval would require the first waiver of the law's principle -- and for the very nation that exploded a nuclear weapon in 1974 and whose government now regularly asserts its right to repeat that event if it so chooses.

Congress, which also plays a role in approving these licenses, must also reassess the Indian exports. For if the safeguards requirements is waived for India, all hope for getting other nations to comply -- Argentina and South Africa, for example -- dissolves.

It has been reported that the president has already assured Prime Minister Indira Gandhi that he will approve the licenses. It will therefore be difficult for him not to. It will be even more difficult, however, for him to explain the undoing, at his hands, of his non-proliferation policy. What is Mr. Carter waiting for -- another Indian bomb?