The US state of Utah began re-opening its national parks Friday after striking a deal with federal authorities, who are discussing similar agreements to unlock landmarks like the Grand Canyon.
At least three other states -- including Arizona, home of the huge canyon -- have reportedly contacted Washington about paying costs themselves as the partial government shutdown drags on.
More than 400 federally-managed tourist sites ranging from California's Yosemite National Park to the Statue of Liberty have been closed since the shutdown started on October 1 due to a budget impasse.
The stalemate is costing $152 million a day in lost travel-related activity, affecting up to 450,000 American workers, according to the US Travel Association. Alone some 20,000 park services employees were furloughed.
Utah struck a deal with federal authorities late Thursday to re-open eight federally-managed parks including Arches, Bryce Canyon and Canyonlands national parks, a spokesman for Utah Governor Gary Herbert told AFP.
"The deal was ... finalized this morning with National Parks signing for Utah's parks to open," said Nate McDonald. "We expect all to be fully open by tomorrow morning."
Under the Utah deal, the state will donate $1.7 million to keep its parks open for 10 days, until October 20. If the federal government shutdown ends before then, Utah will receive a refund.
The Department of the Interior said the National Parks Service "is in the process of negotiating similar agreements with other states."
Media reports identified them as Arizona, Colorado and South Dakota.
"We want to re-open all of our national parks as quickly as possible for everyone to enjoy and call on Congress to pass a clean continuing resolution to open the government," said Interior Secretary Sally Jewell, who spoke to Arizona Governor Jan Brewer on Thursday.
Arizona Republican US Senator John McCain hailed the possibility of a deal to re-open the Grand Canyon, visited by millions of tourists every year.
However, "this proposal will need to be reviewed by Governor Brewer first," he said.
But he added: "We are pleased by reports that the Secretary of the Interior now recognizes that the closure of Grand Canyon National Park has been an economic disaster for northern Arizona and has offered to reopen Grand Canyon National Park using state and private donations."
"Over the past 10 days, the Grand Canyon has been effectively held hostage ... Washington may have time to play this partisan game of chicken, but the people of Arizona do not," he added.
It is unclear whether other states will try to strike deals with Washington.
California, America's most populous state and home to world-famous federally-run tourist attractions including Yosemite and the Alcatraz prison island, has indicated it is too cash-strapped.
"Even if the state were to front general funds for this ... the executive branch cannot unilaterally guarantee that the state would be reimbursed," a spokesman for the state's department of finance told the San Francisco Chronicle.
In Utah, where Bryce Canyon was the first park to fully open Friday, authorities said they had had to act.
"With autumn leaves and mild temperatures, October is a peak month for tourism in many parts of Utah," said the state spokesman, adding that tourism typically makes $100 million in one month alone.
According to Herbert, "Utah's national parks are the backbone of many rural economies and hard-working Utahns are paying a heavy price for this shutdown."
The US Travel Association sent a letter to the White House and Congress on Friday, urging them to work harder to resolve the budget standoff.
"The government shutdown is throttling America's travel sector, which, until now, has been one of the principal drivers of US economic recovery," said its president, Roger Dow.
"Shutting down the government is damaging, and every day the government remains closed compounds the very real consequences."