U.S. Commerce Secretary Wilbur Ross said on Wednesday trade negotiations with China appear to have taken a brief pause.

He also damped expectations that the countries would make substantial progress toward an agreement at an upcoming G-20 meeting.

"I don't know that I would call it a continued impasse. We are where we are. And in any negotiation, there are ups and downs," he told CNBC.  "There are hiatuses and there are much more active periods. So, it appears as though we may be in something of a hiatus now," Ross said.

The United States and China have slapped tit-for-tat tariffs on hundreds of billions of dollars of each other’s goods over the past few months, sparked by Trump’s demands for sweeping changes to China’s intellectual property, industrial subsidy and trade policies.

Trump has frequently accused China of cheapening its currency to gain a trade advantage, claims Beijing has consistently rejected.

The Group of 20 industrialized nations will hold a summit in Argentina next month, and there has been some speculation that U.S. President Donald Trump and Chinese President Xi Jinping could meet about their current trade issues. Treasury Secretary Steven Mnuchin has said no decision has been made for a meeting.

"Meetings of leaders at the G20 never get into huge amounts of detail. Those are meetings that are designed to be broad policy statements," Ross said in the CNBC interview.

He added that many times leaders will talk on the perimeters of the larger summit sessions.

"Generally those are an hour or less in duration and you can't do a multi-thousand page trade agreement in an hour," he said.

Meanwhile, the U.S. Trade Representative’s office told Congress on Tuesday it intends to open trade talks with the European Union, the United Kingdom and Japan.

Under fast-track rules, the United States cannot start talks with the EU, Japan and the United Kingdom until 90 days after notifying Congress.

“We will continue to expand U.S. trade and investment by negotiating trade agreements with Japan, the EU and the United Kingdom,” U.S. Trade Representative Robert Lighthizer said in a statement.

“We are committed to concluding these negotiations with timely and substantive results for American workers, farmers, ranchers, and businesses.”

The letters from Lighthizer to Congress come weeks after the United States won agreement on reworking the North American Free Trade Agreement (NAFTA) with Mexico and Canada, and as the administration faces continuing trade friction with China.

The administration aims to “address both tariff and non-tariff barriers and to achieve fairer, more balanced trade” with the EU and Japan, the letters said.

Japan “is an important but still too often underperforming market for U.S. exporters of goods,” the letter said. It said the United States had a $69-billion trade deficit in goods with Japan, much of that in the auto sector.

In Tokyo, Chief Cabinet Secretary Yoshihide Suga said Japan would protect its interests, based on a joint statement issued at a Japan-U.S. summit on Sept. 26.

“It will not be an easy negotiation,” Suga told a regular news conference.