The economic distress of the nation's farmers trumped 30 years of foreign policy ideology this week as the Senate voted to lift the U.S. embargo on the sale of food and medicine to Cuba.

Farm-state senators from both parties rallied to support an amendment to the $68 billion agriculture spending bill that would lift most unilateral U.S. embargoes on the export of food and medicine to Cuba and other countries. It also would prohibit the president from imposing such bans in the future without the consent of Congress.

If enacted, the measure would sharply curtail use of a standard weapon in the foreign policy arsenal, the denial of access to U.S. agricultural bounty, medicine and medical technology. The House version of the spending bill contains no similar provision, so the outcome will be determined by a House-Senate conference.

"This is a major shift in national policy and an important gain for farmers in Missouri and the rest of the country," said the measure's sponsor, Sen. John D. Ashcroft (R-Mo.). "At a time of drought and financial hardship from low prices, this will protect farmers from being used as pawns of diplomacy."

According to Philip Peters, an analyst of Latin American affairs at the Lexington Institute, a Washington think tank, this is the first time that either house of Congress has voted to ease trade sanctions on Cuba since 1992, when Congress allowed resumption of normal payments for international telephone calls to the island. In effect, Peters added, the Senate has "almost completely dismantled the Cuba food and medicine embargo."

Americans for Humanitarian Trade With Cuba, a coalition of business, religious and legal organizations that has opposed the ban on food and medicine sales to Cuba, hailed the Senate action as "a milestone victory." The group's executive director, Sylvia Wilhelm, a Cuban American, said in a statement that "the Cuban people want and need food and medicine from the U.S. and will applaud this important development."

The debate in the Senate, however, was not centered on Cuba. It was about declining U.S. farm exports worldwide and the desire of agricultural groups to eliminate unilateral food export bans. The Ashcroft amendment does not even mention Cuba specifically--it eliminates unilateral export bans, and thus would also apply to North Korea and other countries listed by the State Department as sponsors of international terrorism.

It would not apply to Iraq or other countries to which sales are restricted by United Nations sanctions.

The Senate passed the farm spending bill by voice vote. In the only recorded vote on the Ashcroft amendment, a move to table it was defeated, 70 to 28.

A Clinton administration spokesman said the White House "is prepared to work with Congress" on crafting the final wording of the bill. Earlier this year, President Clinton modified the Cuba trade embargo to authorize limited sales of food and fertilizer to independent, non-governmental organizations in Cuba.

Advocates of ending the embargo on Cuba said the president's decision has had little if any effect because the only food industry entities in Cuba not controlled by President Fidel Castro's Communist government are small family-owned restaurants with no purchasing power.

The Ashcroft amendment would still require Treasury Department export licenses for sales to countries on the terrorism list, but exporters could obtain general licenses for a year at a time, rather than having to seek a separate license for each transaction.