WASHINGTON (Reuters) - The United States has agreed to reduce some tariffs on Chinese goods and delay a tranche of tariffs that were slated to go into effect on Dec. 15 as part of a trade deal between the two economic giants, a U.S. source familiar with the situation said on Thursday.

China also has agreed to make $50 billion in agricultural purchases in 2020 as part of the deal, that person and another U.S. source familiar with the talks said.