A budget proposed by lawmakers in Congress could further delay launching humans to space from Florida, according to NASA Administrator Charlie Bolden.
Under the current plan, Bodden said, the United States would have to continue relying on Russia to send American astronauts to space.
A Senate appropriations subcommittee on Wednesday approved $900 million for the commercial crew program in the 2016 budget.
That's a lot of money, but NASA officials said it's not enough.
Bolden said both the House and the Senate plan to underfund the efforts of SpaceX and Boeing to build spacecraft capable of sending astronauts to space — starting in 2017.
"By gutting this program and turning our backs on U.S. industry, NASA will be forced to continue to rely on Russia to get its astronauts to space and continue to invest hundreds of millions of dollars into the Russian economy rather than our own," Bolden said in a statement.
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Since the retirement of the space shuttle program, the United States has been paying Russia more than $70 million a seat just to get astronauts to the International Space Station.
Sen. Bill Nelson, D-Florida, said that without the money, the U.S. will have to wait until 2019 before humans can launch from Florida again.
"The money that supposedly is being cut, which is just a little more than $300 million, we would lose that and (we will) still (be) paying that money to the Russians to fly an additional two years," Nelson said. "We need to wake up to what's happening."
Some lawmakers are hoping to restore funding for a commercial crew at the full Senate appropriations committee hearing on Thursday.
In total, the Senate has suggested an $18.3 billion budget for NASA, which is a $279 million increase from last year.