Treasury Secretary Steven Mnuchin told CNBC on Thursday that he and U.S. Trade Representative Robert Lighthizer will talk with Chinese counterparts later in the day but "complicated issues" remain in the trade war.

"This will be the second conversation we've had. There has been conversation at the staff level," Mnuchin said in a "Squawk Box" interview. "We're working under the direction of President Trump and President Xi from the meeting in Osaka and we'll see where we get."

Mnuchin added that if the call went well, he would expect in-person meetings to take place.

China and the U.S. agreed last month at the G-20 summit in Osaka, Japan, to restart trade talks and avoid the implementation of additional tariffs. The world's largest economies have been engaged in a trade war for more than a year, keeping a cloud of uncertainty over financial markets and the global economic outlook.

The Wall Street Journal reported that U.S.-China trade talks have been at a standstill as the Trump administration weighs China's demands to ease restrictions on telecom giant Huawei.

Mnuchin said Huawei was not a sticking point on the negotiations, but "there are just a lot of complicated issues."

"We were very far along [in] the deal. We were disappointed that we went backwards on certain issues," he said. "But if we can get a good deal, this is a great opportunity for U.S. companies and for U.S. workers."

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