"This is an important condition for reaching an agreement", he said.
Tariff reductions in the preliminary deal, which has not yet been confirmed by the American side, could amount to a bargaining win for Beijing.
A Reuters poll of currency strategists on Thursday suggested that the yuan will give up its recent gains and weaken about 2% in six months, in the absence of a broader deal rolling back existing tariffs imposed on China.
U.S. futures had stocks moving to the upside at the start of trading on Thursday as Beijing and Washington agreed to roll back tariffs on each other's goods as part of an effort to secure a phase-one trade deal.
The prospect of an agreement sent stock markets soaring to all-time highs and prompted the International Monetary Fund (IMF) to say a deal easing trade tensions between the United States and China could persuade its officials to revise up forecasts for global growth next year.
Experts said the announcement that existing tariffs would be rolled back in stages was a positive development, but cautioned against over-exuberance, given the repeated reversals in the 19-month-long trade war.
They imposed a 15% tariff on 125 billion dollars worth of goods.
"China has been clear and consistent in its stance toward tariff issues", Gao said.
The trade war between the United States and China has affected the two biggest economies and a world that is dependent on one or both.
Of the countries listed in the report, Taiwan was singled out as the top beneficiary of the trade diversion effects of us tariffs leveled against China.
The increased revenue was the result of the USA levying a new 15 percent tariff on $111 billion of Chinese goods beginning September 1.
China still sees a quick deal is advantageous for it to obtain favorable terms, given the pressure faced by Trump from the impeachment inquiry on the eve of the 2020 election.
China's imports of American soybeans and other goods tumbled more than 26% in the first nine months of this year following tariff hikes and orders to importers to find other suppliers.
The October 12 agreement helped to ease financial market jitters, but the two sides have yet to report progress on major disagreements over technology following 13 rounds of talks.
There is a divide within the administration over whether rolling back tariffs will give away USA leverage in the negotiations, the sources said.