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By David Shepardson

WASHINGTON, July 17 (Reuters) - New U.S. Postmaster General David Steiner told employees he is confident the Postal Service will be able to demonstrate it can operate successfully as an independent agency.

"I am convinced that a strength of the Postal Service resides in our structure as a self-financing independent entity of the executive branch, functioning much like a business but with a public service mission," Steiner said in a message to employees after starting his tenure on Tuesday.

"I am confident that we will be able to demonstrate that the Postal Service can operate successfully under this structure," he added, noting that he wanted to preserve its independence "far into the future."

In February, President Donald Trump called USPS a "tremendous loser for this country," and said he was considering merging the Postal Service with the U.S. Commerce Department , a move Democrats said would violate federal law.

Former Postmaster General Louis DeJoy resigned in March . DeJoy led efforts to restructure the money-losing USPS for nearly five years.

"The Postal Service needs to be on a realistic path to match costs to revenues on a consistent, long-term basis," Steiner told employees.

Steiner, a former CEO of Waste Management WM.N who stepped down as a FedEx FDX.N board member in May after he was announced as the new postal chief, has raised sharp concerns from postal unions because of his ties to a competitor to the Postal Service.

DeJoy led an effort to dramatically restructure the USPS, including cutting forecast cumulative losses over a decade to $80 billion from $160 billion even as mail volumes fell to the lowest level since 1968.

The price of first-class mail stamps rose to 78 cents from 73 cents on Sunday. Stamp prices are up 46% since early 2019, when they were 50 cents.

The USPS, an agency with 635,000 employees that lost $9.5 billion last year, reduced its workforce by 10,000 workers earlier this year through a voluntary retirement program. The USPS in May reported a $3.3 billion net loss for the three months ending March 31.

(Reporting by David Shepardson; Editing by Mark Porter)

((David.Shepardson@thomsonreuters.com; 2028988324;))