Updates at 0255 GMT

BEIJING, March 24 (Reuters) - Chicago soybeans and corn futures slid for a second session on Monday, driven by concerns that U.S. tariffs will dampen the appetite for its farm products.

The most-active soybean contract Sv1 dropped 0.35% to $10.06-2/8 per bushel, while corn Cv1 slipped 0.27% to $4.63 per bushel as of 0255 GMT.

Traders are closely monitoring tariff developments between the United States and its top agricultural trading partners, particularly Canada, Mexico, and China.

The U.S. plans to impose sweeping reciprocal tariffs on multiple trade partners starting April 2, which may include those with Canada and Mexico that have been paused.

U.S.-China tariff tensions have already cut soybean exports, with China retaliating by raising duties on $21 billion in U.S. agricultural products.

As a result, China is expected to shift its soybean purchases to Brazil, which is seeing a bumper harvest.

"Without free access to Mexico and China, and with the risk of a freight penalty on shipments, these factors have all pushed down U.S. domestic prices and futures," said Ole Houe, director of advisory services at IKON Commodities in Sydney.

In Brazil, the soybean harvest is moving swiftly, with 73.84% of the expected 2024/2025 area harvested, up from 69.33% last year, according to Patria Agronegocios.

Meanwhile, wheat Wv1 fell 0.13% to $5.57-4/8 a bushel, partly due to weak demand for U.S. shipments.

Tariff concerns are also dampening market enthusiasm, according to Houe.

Talks between Washington and Moscow on the Ukraine conflict, including Black Sea shipping, have fuelled hopes for smoother Russian and Ukrainian exports.

Russian and U.S. officials will discuss Black Sea transportation safety at peace talks in Riyadh on Monday.

Traders are also positioning ahead of the USDA's grain stocks and prospective planting reports on March 31, where the agency will release estimates for farmers' planting intentions in 2025.

(Reporting by Ella Cao and Mei Mei Chu; Editing by Mrigank Dhaniwala)

((Ella.Cao@thomsonreuters.com;))