American and Chinese senior trade negotiators are expected to resume negotiations in the next week and a half, with much work remaining to reach a comprehensive deal, U.S. Chamber of Commerce Chief Executive Officer Thomas Donohue said.

Lower-level officials from the two nations are scheduled to meet Friday, said Donohue. He spoke to reporters in Washington after U.S. Trade Representative Robert Lighthizer addressed state and local chamber executives Monday.

Bloomberg has reported that administration officials have discussed offering a limited trade agreement to China that would delay and even roll back some U.S. tariffs in exchange for Chinese commitments on intellectual property and agricultural purchases.

Lighthizer and Treasury Secretary Steven Mnuchin last met their Chinese counterpart Vice Premier Liu He in Shanghai in late July. Since then, the U.S. has added tariffs on an additional US$110 billion of Chinese goods, spurring retaliation from Beijing.

Donohue said Lighthizer indicated there’s some movement on China buying U.S. farming products and other issues, but it’s “an extraordinary challenge” to get a complete deal.

The chamber chief executive said while he’s optimistic about an agreement, he’s also a realist and “this is not a simple problem.”

On the North American trade deal, Donohue said negotiations are still happening between Lighthizer and congressional Democrats about proposed changes to the U.S.-Mexico-Canada agreement, which the chamber supports. The USMCA still requires congressional approval to take force.

Lighthizer sent House Democrats a new offer on the stalled agreement last week to resolve concerns over enforcement and other provisions.

“I believe that long before we start looking at the holidays we’ll have this thing done,” Donohue said.