WASHINGTON, April 5 (Reuters) -

U.S. President Joe Biden will visit Baltimore on Friday to survey the site of a collapsed bridge and meet families of the six construction workers who died, amid growing tensions in Congress over using federal dollars to rebuild the bridge.

A cargo ship crashed into the Francis Scott Key Bridge on March 26, sending it collapsing into the harbor. Work to clear the wreckage and restore traffic through the Mid-Atlantic state's shipping channel is ongoing.

Biden's visit, which will include an aerial tour, comes as state and federal officials have raised alarms over the potential economic hardships that the port's closure could have on the regional economy with thousands of port workers already idled.

The Port of Baltimore ranks first in the United States for the volume it handles of autos and light trucks and farm and construction machinery, according to the state of Maryland. Most of that traffic has been suspended since the accident, though some terminal operations outside the affected area have resumed.

Maryland Governor Wes Moore, who will accompany the president on his tour, in television interviews ahead of the visit said cleaning up and rebuilding the bridge is critical for commerce nationwide.

"This is not just impacting Marylanders. This is impacting the farmer in Kentucky. It's impacting the auto dealer in Ohio. It's impacting the restaurant owner in Tennessee. It's impacting the entire country and our economic growth," Moore told MSNBC.

There are signs of friction among some U.S. lawmakers about using new federal dollars to fund the bridge's reconstruction, which federal officials say could cost at least $2 billion.

The White House's Office of Management & Budget (OMB), in a letter to Congress on Friday, asked the federal government to cover the bridge replacement's full cost.

Such a request must pass not only the Democratic-controlled Senate but also the narrowly divided House of Representatives where some Republican hardliners oppose using federal dollars for the project.

The House Freedom Caucus, a bloc of roughly three dozen hardline Republicans who can wield outsized influence over House Speaker Mike Johnson, on Friday issued a series of demands in exchange for their cooperation.

The six victims of the bridge collapse were all immigrants from Mexico and Central America, who were fixing potholes on the road surface of the bridge when it collapsed. Four of the bodies have still not been recovered, but all are presumed dead.

Biden's meeting with the families of these immigrant workers comes as his rival Republican presidential nominee Donald Trump has ramped up anti-immigrant rhetoric and cast migrants as dangerous criminals "poisoning the blood" of America.

FUNDING FOR THE BRIDGE

Hours after the bridge collapse, Biden said the U.S. government would "pay the entire cost" of reconstruction and his administration announced $60 million in emergency relief last week.

The administration will pursue all avenues to recover costs and "ensure that any compensation for damages or insurance proceeds collected will reduce costs for the American people," OMB Director Shalanda Young wrote on Friday.

White House officials have held talks in recent weeks with Johnson's office over billions in aid for Ukraine and Israel as well as money for the collapsed bridge, according to two officials familiar with conversations who asked not to be named.

The spending measures separately have bipartisan support, but the White House is aware that Johnson must satisfy his hardline colleagues, which means many of these spending proposals will be tethered together in order to pass, the officials said.

The Freedom Caucus, whose members helped oust Johnson’s predecessor last year, said Congress should seek “maximum liability” from foreign shipping companies.

It also demanded that any aid be fully offset with spending cuts and that the Endangered Species Act and other regulations are waived to avoid delays. It also called on the Biden administration to lift its pause on liquefied natural gas exports.

Attorneys for the companies that own and manage the container ship that crashed into the bridge have asked a judge in federal court to excuse them from any liability for the disaster or, alternately, cap damages at $43 million, the cost of the vessel minus damage and salvage.

Meanwhile, top White House officials have urged large employers in the Baltimore area to retain workers, the White House said, with local employers, including United Parcel Service, Amazon.com, Home Depot and Mercedes-Benz committing to keep their area employees.

The Small Business Administration has also made low-interest disaster loans available, and Biden's supply chain task force has met several times to analyze the impact, "which has so far been manageable," a White House official said.

Moore, on CNBC, said the U.S. Army Corp of Engineers estimates a deeper shipping channel can open within a month — "a significant milestone" to handle autos — and another deeper channel one month later. U.S. Transportation Department on Friday also moved to increase cargo handling at another Baltimore site unaffected by the bridge collapse.

(Reporting by Nandita Bose in Washington, Additional reporting by Jarrett Renshaw, Rick Cowan; David Morgan, Susan Heavey and Daniel Trotta; Editing by Mary Milliken, Sonali Paul and Chizu Nomiyama)