"We're making progress in negotiating on the grandest scale between the two countries ever, we're covering everything," Kudlow told reporters.

"It's going to take time. We are moving," he said. "I'd love to make a deal. I'm a free trader but it's got to be a great deal."

Chinese Vice Premier Liu He will visit the United States on Jan. 30 and 31 for the next round of trade negotiations with Washington.

Liu's visit follows lower-level negotiations held in Beijing last week to resolve the bitter dispute between the world's two largest economies by March 2, when the Trump administration is scheduled to increase tariffs on $200 billion worth of Chinese goods.

(Reporting by Eric Beech; Editing by Lisa Lambert)