Phone calls between top officials from U.S. and China have brought the two countries close to finalizing parts of the “phase one” trade deal announced in mid-October, the Office of the U.S. Trade Representative said Friday.

U.S. Trade Representative Robert Lighthizer and Treasury Secretary Steven Mnuchin have recently talked with Chinese Vice Premier Liu He, China’s chief trade negotiator, the U.S.T.R. office said in a statement to CNBC.

“They made headway on specific issues and the two sides are close to finalizing some sections of the agreement,” the U.S.T.R. said, according to CNBC. “Discussions will go on continuously at the deputy level, and the principals will have another call in the near future.”

There were no details on which issues had been resolved.