House Democrats are making a last-ditch effort to help the flailing airline industry avert tens of thousands of layoffs on Oct. 1, tucking into their latest COVID-19 aid bill $25 billion to extend payroll support for passenger airlines through next March.

The measure released late Monday would extend the airline payroll support provision that was included in a $2 trillion coronavirus relief law passed by Congress in March.

Passenger airlines received $25 billion in payroll support grants in that law, but the money expires Sept. 30, and carriers including United Airlines and American Airlines have said they will have no choice but to furlough employees if the aid is not renewed.

[White House backs $25B airline relief extension]

United in July estimated it could furlough 36,000 employees, and American has said it will have to furlough some 17,500 and lay off 1,500 on the management side.

But on Monday, United pilots announced they had reached an agreement with management that would keep all 13,000 United pilots employed and cancel the 2,850 previously announced pilot furloughs. United still estimated 12,000 layoffs to front-line staff would occur if aid is not renewed.

The House bill introduced Monday would also extend $3 billion in payroll support for airline contractors as originally approved in March, as well as $300 million to cargo airlines. The March law included $4 billion for cargo airlines, but they have used a fraction of that money.

The House bill also includes $32 billion for transit, which has seen ridership plummet amid the pandemic — an offer that matches what the American Public Transportation Association has said its members will need to survive. Of that amount, $28.5 billion would be for operating assistance grants.

It also includes $13.5 billion in economic relief to airports and $75 million to preserve passenger air service for smaller communities. And it includes $2.4 billion for Amtrak, including $569 million to help states and commuter rail providers pay Amtrak for state-supported route and commuter rail use of Amtrak’s Northeast Corridor.

The bill is not expected to receive a Senate vote as introduced but instead is yet another effort to engage Republicans in further negotiations on COVID-19 relief before the Nov. 3 elections. The measure is $1 trillion less expensive than the House bill that passed in May. That bill did not include an extension of airline relief.

Airlines have partnered with labor unions in recent days to stress the urgency of renewing the airline payroll support. Last week, Senate Commerce, Science and Transportation Chairman Roger Wicker, R-Miss., and Senate Transportation-HUD Appropriations Chairwoman Susan Collins, R-Maine, introduced a bill to extend the aid through March.

The Senate bill would provide $25.5 billion for passenger air carriers, $300 million for cargo air carriers and $3 billion for contractors.

Lawmakers have been largely united in the need to further extend support for airlines, in large part because layoffs could further rattle a shaky economy. In a January report released before the pandemic largely shut down aviation, the Federal Aviation Administration said civil aviation accounts for about 5 percent of the U.S. economy, contributing $1.8 trillion in total economic activity and supporting nearly 11 million jobs.

Both White House Chief of Staff Mark Meadows and Treasury Secretary Steven Mnuchin have publicly endorsed extending the payroll grants. And 16 GOP senators, including Wicker and Collins, who is up for reelection in November, wrote to Senate leaders in August urging continuation of the program.

In the House, 223 lawmakers from both sides of the aisle have requested a six-month extension of the politically popular program.