Updated

President Trump reignited his feud with Amazon on Saturday arguing that the online retailer’s “scam” shipping deal with the U.S. Postal Service is costing the agency “billions of dollars.”

“It is reported that the U.S. Post Office will lose $1.50 on average for each package it delivers for Amazon. That amounts to Billions of Dollars,” Trump said over two tweets. “If the P.O. ‘increases its parcel rates, Amazon’s shipping costs would rise by $2.6 Billion.’ This Post Office scam must stop. Amazon must pay real costs (and taxes) now!”

The tweets suggest Trump got his information from The New York Times and attack the “Fake Washington Post,” which continues to be critical of Trump’s administration and is owned by Jeff Bezos, the founder of Amazon.

The president’s tweets on Saturday also suggest Amazon is not paying its fair share of sales tax and that the Post’s “lobbying staff” has “ballooned” in efforts to keep favorable tax laws and the Postal Service deal.

However, federal regulators have found the contract with Amazon to be profitable.

“I have stated my concerns with Amazon long before the Election,” Trump tweeted Thursday. “Unlike others, they pay little or no taxes to state & local governments, use our Postal System as their Delivery Boy (causing tremendous loss to the U.S.), and are putting many thousands of retailers out of business!”

The Post and Bezos have responded to Trump's lobbyist claims in the past by declaring that Bezos is not involved in any journalistic decisions at the paper.

Amazon.com, Inc., and the newspaper declined to comment Saturday.

Amazon lives and dies by shipping, and an increase in the rates it pays could certainly do some damage. Amazon sends packages via the post office, FedEx, UPS and other services.

But while the U.S. Postal Service has lost money for 11 years, package delivery -- which has been a bright spot for the service -- is not the reason.

Boosted by e-commerce, the Postal Service has experienced double-digit increases in revenue from delivering packages, but that hasn't been enough to offset pension and health care costs as well as declines in first-class letters and marketing mail.

Together, letters and marketing mail make up more than two-thirds of postal revenue.

In arguing that the Postal Service is losing money on delivering packages for Amazon, Trump appears to be citing some Wall Street analysis that argue the Postal Service's formula for calculating its costs is outdated. A 2017 analysis by Citigroup did conclude that the Postal Service was charging below market rates as a whole on parcels.

Still, federal regulators have reviewed the Amazon contract with the Postal Service each year and determined it to be profitable.

The Associated Press contributed to this report.