Trade talks between the United States and China made “good headway” last week in Beijing and the two sides aim to bridge differences during talks that could extend beyond three days this week, White House economic adviser Larry Kudlow said.

Kudlow, speaking to reporters on Wednesday at an event organized by the Christian Science Monitor, said China had recognized problems for the first time during the talks that the United States has raised for years.

Negotiations continued in Washington on Wednesday after meetings last week in Beijing, spearheaded by U.S. Trade Representative Robert Lighthizer and Treasury Secretary Steven Mnuchin.

President Donald Trump will meet Vice Premier Liu He, who is leading the Chinese side in the talks, in the Oval Office at 4:30 p.m. (2030 GMT) on Thursday, the White House said.

A date for a meeting between Trump and Chinese President Xi Jinping could be announced as early as Thursday, Bloomberg and the Wall Street Journal reported, citing unidentified sources, which would signal that a deal could be close. But the WSJ, citing an administration official, said discussions remained fluid and those plans could change.

Asked about the potential for a meeting between the presidents, China’s Foreign Ministry told a news briefing on Thursday that it had noted that Trump had repeatedly expressed his hope to meet with Xi.

“President Xi also looks forward to maintaining communication with President Trump in all kinds of ways,” ministry spokesman Geng Shuang said without elaborating.

The United States and China have levied tariffs on hundreds of billions of dollars’ worth of two-way trade since July 2018. Trump has said he wants a “great deal” with China and has hinted that tariffs could remain in place for some time.

Chinese commitments to increase purchases of American agricultural, energy and manufactured products are expected to be part of a final deal, and a person familiar with the talks said China would get about six years to meet those commitments, or until 2025.

The deadline was reported earlier by Bloomberg, but Trump administration officials previously said that a six-year timeline for purchases exceeding $1 trillion had been under discussion.

A final number for the amount of purchases has not been settled, the person said.

Kudlow said Liu and his team would remain in Washington for three days and possibly longer.

“We’re covering issues that have never really been covered before, including enforcement,” Kudlow said, listing U.S. accusations that Beijing engages in intellectual property theft, forced transfer of technology from U.S. companies doing business in China, cyber hacking, tariffs and non-tariff barriers for commodity trading.

“All making good progress, all making good headway, but we’re not there yet,” he said about those areas. “We hope this week to get closer.”

Kudlow said it was significant that China had “acknowledged these problems for the first time. They were in denial.”

Those structural issues along with the way a potential deal would be enforced have been sticking points during months of talks between the world’s two largest economies.

Kudlow said on Wednesday that U.S. charges against Chinese telecommunications giant Huawei Technologies Co Ltd had generally not come up during trade talks.

Kudlow also said no decisions had been made on tariffs on auto imports coming from top U.S. allies.