(CNN) - President Donald Trump complained on Thursday that China hasn't yet begun purchasing US agricultural products -- a sign that some of the commitments he believed were made with Chinese President Xi Jinping last month weren't as solid as advertised.
"Mexico is doing great at the Border, but China is letting us down in that they have not been buying the agricultural products from our great Farmers that they said they would. Hopefully they will start soon!" Trump wrote on Twitter.
The tweet is reflective of what people familiar with the talks say were loose agreements Trump secured during his 90-minute meeting last month with Xi. But according to people familiar with the talks, the Chinese side has said they made no firm commitments to purchase US agricultural products, despite Trump's claims otherwise after the meeting.
"China is going to be buying a tremendous amount of food and agricultural product, and they're going to start that very soon, almost immediately. We're going to give them lists of things that we'd like them to buy," Trump said at the time.
In exchange, Trump agreed to forestall new tariffs on Chinese products and ease some restrictions on Huawei, the Chinese telecom giant. Without the new agricultural purchases, it's not clear what Trump is getting in return for those moves.
This isn't the first time Trump had claimed that China was going to buy more agricultural products. He said the same in December when the two countries came to a temporary trade truce, and Agriculture Secretary Sonny Perdue tweeted in February that China was going to buy 10 million metric tons of soybeans.
But Department of Agriculture data shows those pledges haven't come to fruition.
The United States has exported about 8.3 million metric tons of soybeans to China through last week. That's only about a quarter of the 31.7 million metric tons that were exported to China in 2017, before trade tensions escalated.
China, once the biggest market for US soybean farmers, stopped buying the American product last summer in retaliation to Trump's tariffs. By the end of 2018, the amount of America soybeans sitting in storage hit record levels.
Now that the trade spat has lasted a year, many farmers worry they won't ever get the Chinese market back because they've started buying from other countries.
"The Chinese market is something we've built up over years, and it's been washed away in a short time," said Marcy Svenningsen, who grows soybeans, corn and wheat in North Dakota.
"Even if they sign a trade agreement tomorrow and lift tariffs, I don't believe we'll have the market back," she added.
Chinese negotiators saw buying American farm products as contingent on steps toward a larger trade deal, according to the people familiar with the negotiations. They did not believe there were specific commitments -- including quantities -- that were agreed to in the discussions.
On Thursday morning, the President's economic adviser Larry Kudlow told reporters the US still expected major purchases from Beijing.
"I know that our side expects China very soon to start purchasing American agriculture, commodities, crops, goods and services," Kudlow said at the White House.
This week, US Trade Representative Robert Lighthizer and Treasury Secretary Steven Mnuchin spoke with Chinese Vice Premier Liu He and Commerce Minister Zhong Shan by telephone. It's believed they will travel to Beijing in the next several weeks to resume in-person talks.