In April, the space agency awarded the $2.9 billion contract to Elon Musk, rejecting a bid from Bezos' company Blue Origin.
NASA seems to be in the position of worrying about which rich white guy is going to spend all the money they got on tax breaks to try and get their names in the history books in a capitalistic space race.
The award is for building the landing system that will carry astronauts down to the lunar surface as early as 2024.
NASA could only award the contract to one company, not two as expected because of a funding shortfall.
The space agency had received only $850 million of the $3.3 billion it requested from Congress to build the Moon lander.
In a letter to NASA's administrator Bill Nelson, released on Monday, Bezos wrote: "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 programme back on track right now.
"This offer is not a deferral but is an outright and permanent waiver of those payments".
SpaceX's winning bid will use an adapted version of its Starship vehicle to land astronauts on the Moon
Their design was named the Blue Moon lander and bore a passing resemblance to a beefed-up version of the lunar module (LM) that carried Neil Armstrong and Buzz Aldrin to the surface in 1969.
In his letter, Bezos emphasised Blue Moon's proven heritage: "We created a 21st Century lunar landing system inspired by the well-characterised Apollo architecture - an architecture with many benefits. One of its important benefits is that it prioritises safety" whereas we guess he thinks that Musk's design prioritises Musk.
Musk's Starship is billed as "pushing the envelope of spacecraft design", employing a "radical approach to landing" and incorporating "innovative methane-fuelled engines."
Bezos used his letter to emphasise Blue Origin's use of hydrogen fuel, which dovetails with Nasa's longer-term aims of refuelling spacecraft from water-ice mined on the Moon. The water can be split into hydrogen and oxygen propellant for rocket engines.
