To be reconsidered for a key contract to build a Moon landing vehicle, Jeff Bezos has offered to cover $2 billion (£1.4 billion) in Nasa costs.
NASA awarded Elon Musk the $2.9 billion contract in April, rejecting a bid from Jeff Bezos' Blue Origin.
The award is for the development of a landing system that will transport astronauts to the lunar surface as soon as 2024.
Due to a funding shortfall, Nasa was only able to award the contract to one company rather than the expected two.
The space agency had only received $850 million of the $3.3 billion requested by Congress for the Moon lander's construction.
"Blue Origin will bridge the HLS [Human Landing System] budgetary funding shortfall by waiving all payments in the current and next two government fiscal years up to $2 billion to get the program back on track right now," Mr. Bezos wrote in a letter to Nasa administrator Bill Nelson, which was released on Monday.
"This offer is an outright and permanent waiver of those payments, not a deferral."
Nasa's human exploration chief Kathy Lueders admitted at the time of the award that the space agency's current budget prevented it from selecting two companies.
Elon Musk's SpaceX firm's track record of orbital missions was also cited by Nasa as a factor in the award. Cost is thought to have played a role as well: SpaceX's bid was the cheapest by a long shot.
As a result of the decision, Nasa's first mission to the lunar surface since Apollo 17 in 1972 will be carried out by SpaceX's cylindrical Starship vehicle.
Dynetics, a defense contractor based in Alabama, was also vying for the contract.
Bezos teamed up with aerospace behemoths Lockheed Martin, Northrop Grumman, and Draper in an attempt to join Nasa's Human Landing System programme at this critical stage.
The Blue Moon lander was their creation, and it looked a lot like a beefed-up version of the lunar module (LM) that brought Neil Armstrong and Buzz Aldrin to the surface in 1969.
Bezos emphasized Blue Moon's provenance in his letter: "We designed a 21st-century lunar landing system based on the well-known Apollo architecture, which has numerous advantages. One of its most significant advantages is that it places a high priority on safety."
Musk's Starship has pushed the boundaries of spacecraft design by taking an unconventional approach to landing and incorporating cutting-edge methane-fueled engines.
In his letter, Bezos also emphasized Blue Origin's use of hydrogen fuel, which aligns with Nasa's long-term goals of refueling spacecraft with water ice mined on the Moon. Water can be split into hydrogen and oxygen, which can be used as the propellant in rocket engines.
SpaceX received an "acceptable" technical rating and an "outstanding" management rating in Nasa's April selection statement. Blue Origin's bid was also rated "acceptable" on technical grounds, but the space agency gave it a "very good" management rating.
Blue Origin filed a protest with the US Government Accountability Office (GAO) after losing out to SpaceX, alleging that Nasa unfairly "moved the goalposts at the last minute" in awarding the contract to SpaceX.
That protest, along with one filed by Dynetics, is still pending, though some in the space community believe a reversal is unlikely.