The United States and China launch a critical round of trade talks on Wednesday amid deep differences over Washington’s demands for structural economic reforms from Beijing that will make it difficult to reach a deal before a March 2 U.S. tariff hike.

The two sides will meet next door to the White House in the highest-level talks since U.S. President Donald Trump and Chinese President Xi Jinping agreed a 90-day truce in their trade war in December.

People familiar with the talks and trade experts watching them say that, so far, there has been little indication that Chinese officials are willing to address core U.S. demands to protect American intellectual property rights and end policies that Washington says force U.S. companies to transfer technology to Chinese firms.

The U.S. complaints, along with accusations of Chinese cyber theft of U.S. trade secrets and a systematic campaign to acquire U.S. technology firms, were used by the Trump administration to justify punitive U.S. tariffs on $250 billion worth of Chinese imports.

Trump has threatened to raise tariffs on $200 billion of goods to 25 percent from 10 percent on March 2 if an agreement cannot be reached. He has also threatened new tariffs on the remainder of Chinese goods shipped to the United States.

"Clearly on the structural concerns, on forced technology transfer, there remains a significant gap if not a wide chasm between the two sides,” a person familiar with the talks told Reuters.

Chinese officials deny that their policies coerce technology transfers.

They have emphasized steps already taken, including reduced automotive tariffs and a draft foreign investment law that improves access for foreign firms and promises to outlaw "administrative means to force the transfer of technology.”

China is fast-tracking that new law, with the country’s largely rubber-stamp parliament likely to approve it in March.

A crucial component of any progress in the talks, according to top administration officials, is agreement on a mechanism to verify and "enforce” China’s follow-through on any reform pledges that it makes. This could maintain the threat of U.S. tariffs on Chinese goods long term.

Some business groups watching the talks were tempering expectations for a breakthrough this week.

With a month to go before the deadline, it was unlikely that the best offers from either side would be put on the table in the next two days, said Erin Ennis, senior vice president of the U.S.-China Business Council.

"I don’t think there’s going to be any big outcome,” Ennis said of the talks scheduled for Wednesday and Thursday.

"Hopefully they make some good progress that will set them up to be able to get to completion at the end of the 90 days.”

But the Chinese side, led by Vice Premier Liu He, would likely have to bring to the table a new offer that goes significantly beyond its previous offers to significantly increase purchases of U.S. goods, including soybeans, energy and manufactured goods.

People familiar with the talks said manufactured goods, a key priority for the Trump administration, were among the largest components of Chinese purchase pledges aimed at significantly reducing the U.S. trade deficit with China. But here, too, there are "no guarantees” that Beijing would follow through on these pledges, one of the people said.

Also hanging over the talks are U.S. indictments against Chinese top telecommunications equipment maker Huawei Technologies Co, accusing it of bank and wire fraud to evade Iran sanctions and conspiring to steal trade secrets from T-Mobile US Inc.

U.S. Treasury Secretary Steven Mnuchin, one of the Trump administration’s strongest advocates for a deal with China, made upbeat comments about the talks for a second day in a row on Tuesday.

Mnuchin said on Fox Business Network that he expects "significant progress” on market access and technology transfer issues. He insisted that the Huawei case and trade talks were "separate issues.”

Meanwhile, earnings warnings from U.S. companies hit by the slowdown in China’s economy - due in part to the tariffs - are piling up. 3M Co joined Caterpillar, Nvidia and Apple to blame weakening Chinese demand for revenue and profit shortfalls.

It will get worse for both U.S. and Chinese firms and financial markets if Washington and Beijing cannot show enough progress to at least delay the March 2 tariff deadline, said Nicholas Lardy, a senior fellow and China trade expert at the Peterson Institute for International Economics in Washington.

"Given the weakness in the Chinese economy and the fact that the U.S. will certainly be slowing down, that’s not a pretty picture,” Lardy said.

Agencies.