(Bloomberg) -- Amazon.com Inc.’s contract with the U.S. Postal Service for package delivery shows that President Donald Trump’s attacks on the company "are inaccurate," two congressional Democrats wrote in a letter to the president.

Deals between the Post Office and the retail giant as well as "other retailers have been one of the few areas of growth in Postal Service revenues, experiencing double-digit increases in recent years and accounting for nearly 30 percent of its operating revenue in fiscal year 2017," Representatives Elijah Cummings of Maryland and Gerald Connolly of Virginia said in their letter, which they released on Wednesday.

As part of a series of attacks against the company, Trump tweeted on April 3 that Amazon is "costing the United States Post Office massive amounts of money for being their Delivery Boy."

Later in April, he issued an order that would establish a commission -- to be led by Treasury Secretary Steven Mnuchin -- to examine the Postal Service’s finances, including its relationship with shippers like Amazon and the prices it charges them. The order didn’t mention Amazon, but it was interpreted as a first step toward turning the president’s rhetorical attacks on the company into policy.

Trump issued the order after his campaign manager, Brad Parscale, had complained to him that taxpayers were subsidizing the company at the expense of small businesses, according to a person familiar with the matter. Trump has also linked his complaints to the Washington Post, which has been critical of his administration and is owned by Amazon’s Chief Executive Officer Jeff Bezos.

Package Deals

Amazon regularly uses the Postal Service to complete what’s called the “last mile” of delivery, with letter carriers dropping off packages at some 150 million residences and businesses daily.

Cummings and Connolly wrote that Amazon "is not receiving any preferential treatment from the Postal Service." The lawmakers said that they had seen the agreement but, at the request of the Postal Service, were not releasing the contract as it contains "confidential business information."

"The allegations you have made about Amazon and the Postal Service are inaccurate," added Cummings and Connolly, the top Democrats on the House Oversight Committee and its subcommittee on government operations.

The company, they said, "is paying package delivery rates comparable to FedEx and UPS," which also have delivery agreements with the Postal Service.

Representatives of the White House and Amazon didn’t immediately respond to requests for comment on Wednesday evening.

To contact the reporter on this story: Ben Brody in Washington at btenerellabr@bloomberg.net

To contact the editors responsible for this story: Sara Forden at sforden@bloomberg.net, John Harney

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