CHICAGO, Jan 19 (Reuters) - The U.S. Department of Agriculture (USDA) on Friday confirmed private sales of 297,000 metric tons of U.S. soybeans to China, the first soybean sales announcement under its daily reporting rules since Dec. 19 and the first to the world's top buyer of the oilseed since Dec. 15.

The sales announcement came a day after U.S. Agriculture Secretary Tom Vilsack met with China's Minister of Agriculture and Rural Affairs, Tang Renjian.

The booking also follows a 6% slide in Chicago Board of Trade (CBOT) soybean futures since the start of the calendar year, with the benchmark contract dipping to $12.01 a bushel this week before stabilizing in early moves on Friday.

Soybean futures have sagged on improved crop weather in Brazil, the largest global producer and exporter, following weeks of drought, although Brazilian production prospects remain uncertain.

Brazilian supplies are due to flood the market over the coming weeks as more soybeans are harvested. Exporters there are offering shipments in February and beyond at prices $1.50 or more below U.S. soybeans, analysts and exporters said.

Meanwhile, the USDA's Jan. 12 estimates of U.S. 2023/24 soybean production, ending stocks and Dec. 1 stockpiles all were above most trade expectations, easing supply concerns.

China has booked 20.2 million metric tons of U.S. soybeans so far in the 2023/24 marketing year that began Sept. 1, down from 27.2 million tons a year ago.

The USDA has projected China's global 2023/24 soybean imports at 102 million tons, up from 100.85 million in 2022/23. However, a recent downturn in China's massive hog sector is expected to reduce first-quarter Chinese soybean imports to a four-year low.

(Reporting by Julie Ingwersen; additional reporting by Karl Plume Editing by Marguerita Choy)