The U.S. will temporarily exempt more than 400 types of Chinese products from tariffs imposed by President Donald Trump's administration last year, according to three notices published on Friday by the Office of the U.S. Trade Representative (USTR).

The exemptions include products like Christmas tree lights, plastic straws, dog leashes and printed circuit boards, for a total of 437 product types. They came from more than 1,100 exclusion requests made by U.S. companies and other entities, according to the documents.

The exemptions will be introduced in three batches based on when tariffs came into effect in 2018. Exclusions from a total product list of 34 billion U.S. dollars will apply retroactively from July 6, 2018; exclusions from a 16-billion-U.S.-dollar list will apply retroactively from August 23, 2018; and exclusions from a 200-billion-U.S.-dollar list will apply retroactively from September 24, 2018.

The exclusions will extend for a year from the date of their announcement for products from the 34-billion-U.S.-dollar and 16-billion-U.S.-dollar product lists, but only extend until August 7, 2020 for products from the 200-billion-U.S.-dollar product list, said the USTR.

Escalation not desirable for both sides

The world's two largest economies have been locked in an escalating trade friction for more than a year, during which the Trump administration repeatedly levied tariffs on China, which responded in kind.

"The latest exemptions are a tacit acknowledgement by the U.S. of the damage being done to domestic interests by the imposition of tariffs," CNBC quoted Stephen Olson, research fellow at the Hinrich Foundation, as saying.

"The timing however is interesting...It suggests that both sides have determined that further escalations are not desirable right now, so they are trying to create positive atmospherics before the October round of negotiations, in the hopes that those talks will at least forestall any further deterioration."

Creating good vibes for trade talks

The announcement of the exemptions coincided with meetings by mid-level U.S. and Chinese officials in Washington in preparation for the 13th round of trade talk expected in October.

China and the United States held vice ministerial-level trade talks on Thursday and Friday, and conducted constructive discussions on economic and trade issues of mutual concern.

Last week, China announced it would exempt the first set of 16 U.S. goods from the first round of additional tariffs and President Trump subsequently postponed additional five percent tariffs on 250 billion U.S. dollars of Chinese imports from October 1 to 15. Following that, China added soybeans and pork imports to its tariff exemption list.