Food shoppers in South Korea, Mexico and Japan are fueling a surge in U.S. beef prices just as demand is set to reach a seasonal peak this month and retailers including Sam's Club promote the meat in stores.

Retail beef rose to a record $4.453 a pound in April, up 11 percent from a year earlier, after all-time highs the previous four months, the U.S. Department of Agriculture said today. Supplies have tightened as South Korea tripled imports of U.S. beef in the first quarter from a year earlier, and Japan's purchases rose 63 percent, data show.

Costs are gaining at a time when consumers usually boost purchases by 25 percent from April 1 to the end of May, when warmer weather encourages grilling outdoors, the National Cattlemen's Beef Association said, citing data from FreshLook Marketing Group LLC. The three-day weekend that includes the Memorial Day holiday on May 30 is usually the busiest for sales, the Livestock Marketing Information Center estimates.