WASHINGTON (Reuters) -The U.S. Postal Service Board on Friday said it named David Steiner, a FedEx ( FDX ) board member and former CEO of Waste Management, as the new postmaster general after the White House pressured the prior leader to resign in March.

Postal unions have raised sharp concerns about Steiner's selection to succeed Postmaster General Louis DeJoy because he sits on the board of a competitor to the Postal Service. The Postal Service reported a wider net loss of $3.3 billion for the three months ending March 31 as it continues to hike stamp prices and seek ways to cut costs.

"I believe strongly in maintaining its role as an independent establishment of the executive branch," Steiner said in a statement released Friday. The board said it expects him to start in July, and that he will leave the Board at FedEx ( FDX ).

USPS said on Friday its controllable loss was $848 million, up from $317 million in the same quarter last year as mail volume continued to fall. In February, President Donald Trump called the agency a "tremendous loser for this country" and has said is considering merging the Postal Service with the U.S. Commerce Department. Democratic lawmakers have said such a move would violate federal law.

The White House did not immediately comment Friday.

American Postal Workers Union President Mark Dimondstein told Reuters this week that Steiner was the wrong choice. "You don't put the fox in charge of guarding the hen house," Dimondstein said, adding it was "an abdication of their duty to remain independent of this administration."

FedEx ( FDX ) Executive Chairman Fred Smith praised Steiner's selection.

"David's sharp business acumen will be key to addressing the significant challenges facing the United States Postal Service," Smith said, noting USPS has lost more than $108 billion since 2007.

"The USPS must be reformed to improve service, to no longer rely on taxpayers to subsidize its operations, and to be held accountable to the same rules as private sector companies."

Democratic lawmakers for years called for DeJoy to be fired but agreed to give USPS $50 billion in financial relief in 2022.

DeJoy led an effort to dramatically restructure USPS over the last five years, 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.