Major import companies from China have loaded up on their purchases of agricultural products from the US as the two countries head back to the negotiating table to iron out their longstanding trade differences.

The increase in Chinese imports includes another series of soybean contracts and the country's biggest weekly shopping list of US pork, latest data showed Thursday.

Some 400,000 tons of soybeans have been shipped by private exporters to mainland China, based on figures released by the Department of Agriculture. The delivery marks what economists refer to as the second daily "flash sale" of soybeans in a week to the leading soybeans consumer in the world.

The flash orders also represent over 1 million tons of total soybean sales to the Chinese market, the USDA confirmed, for the week covering October, and the biggest sales of pork at almost 11,000 tons of orders for the current year. An estimated 124,000 tons of pork will be shipped to China next year.

The new set of agreements were made ahead of top-level trade meeting between Washington and Beijing that began Thursday intended to put closure to their 15-month economic spat that has jolted finance hubs around the world and cut US farm output to China.

American pork sales to China had been generally poor in the past few months after outlook for bulk purchases. Local prices of basic goods in the mainland are up as the African swine fever virus wreaked havoc on the country's swine industry, denting supplies of the country's favorite commodity.

According to independent US economic analyst Bob Brown, such volume of agricultural products sales have never happened before. "Right now, our prices are very modest compared to Europe, which is China's other major supplier," he said.

Chinese commerce ministers have implemented huge taxes on US pork imports as a form of retaliation for American duties on China's products, but US prices still look appealing despite the current 73 percent tax, analysts said.

Sales of American soybean have likewise soared ahead of the scheduled meetings in Washington in at least four tranches of aggressive purchases since the first days of September. China has granted some importers waivers to purchase US soybeans that allow imports without requiring high retaliatory taxes.

The Chinese has imported over 13 million tons of American soy last year up to the early months of 2019 and has purchased almost 5 million tons more in the last quarter, the USDA reported.