"If negotiations are successful, the administration is prepared to rescind the notice of withdrawal and remain in the UPU", White House spokeswoman Sarah Sanders said in a statement.
The unfair global postal rates, according to the official, also are being used by China to ship counterfeit goods and narcotics, such as fentanyl, to the United States.
Trump and China's President Xi Jinping may meet during the G20 summit in Buenos Aires, Argentina, on November 30 to December 1, and the topic of shipping rates is certain to be on the agenda if they do.More news: Drug-impaired driving concerns as Canada legalises cannabis
The move will most likely inflame tensions with China, which the administration has accused of unfair trade practices and punished with tariffs on $250 billion worth of Chinese goods, investment restrictions and other measures.
Officials stressed that the goal is not to leave the UPU, even as they announced Trump's intention to withdraw from the treaty. The biggest winners could be shipping carriers such as UPS. But Navarro and Trump dismissed those changes as insufficient to deal with the explosion of online free shipping offers of goods from China.
USA manufacturers applauded the move. Efforts will continue to renegotiate the rates during the year, but The New York Times reported the us will "self-declare" new rates to be charged on shipments from China to this country.
The price of shipping a 4.4-pound package, the largest parcel covered by the treaty, from China to the United States is about $5, according to US estimates.More news: Nacho Cheese or Cool Ranch? Doritos lure rogue pig back home
From now on, the United States will have "self-declared rates" for packages under 2 kilograms (4.4 pounds) to correct what US officials call a "major economic distortion".
They argued that the treaty allows foreign postal services, especially in China but also in Germany, to take advantage of cheap shipments to the US.
The group said the discounts amount to a subsidy for Chinese shippers that cost the U.S. Postal Service $170 million in 2017. A 2014 study, cited in a Postal Service analysis of the issue, estimated that discounted shipping cost industrialized nations as much as $2.1 billion a year in aggregate.
President Trump argues the growth in Chinese exports to the USA has destroyed American jobs.More news: Fed signals more rate hikes despite emerging market 'stress'
"This outdated arrangement contributes significantly to the flood of counterfeit goods and unsafe drugs that enter the country from China". The fact is, through the bilateral trade agreement with the United States, you know how much benefit American consumers have got with trade with China over the years and how much money American companies have made from operating in China. "How can my government be subsidizing China and driving me out of business?"