A new report has outlined several roadblocks facing the U.S. for potentially sending astronauts to explore Mars.

According to CBS News, the new National Research Council (NRC) report states the U.S. may not be able to send astronauts to Mars until mid-century, if at all. The report further stated the U.S. will need more funding in the long run, continued government support and international participation.

The panel did not close the door on exploring Mars, but it did state that the goal should be long-term, as the Red Planet and its moons are about as far out as humans could feasibly explore.

"The technical analysis completed for this study shows that for the foreseeable future, the only feasible destinations for human exploration are the moon, asteroids, Mars, and the moons of Mars," Jonathan Lunine, NRC co-chair, said in a press release. "Among this small set of plausible goals, the most distant and difficult is putting human boots on the surface of Mars, thus that is the horizon goal for human space exploration. All long-range space programs by our potential partners converge on this goal."

The report offered a suggestion for the U.S. to conduct a moon exploration mission as a "pathway" to a Mars mission. The NRC panel stated putting astronauts on the moon again could drum up support from the public, government and potential international participants.

The panel did acknowledge that the general public would welcome space exploration beyond the moon, but that support would waver when faced with the large budget increase necessary.

"We believe the public will support it, we believe the rationales justify it, we believe the achievement would be monumental," Mitch Daniels, panel co-chair, said during a briefing. "But we think there is really one, and possibly only one way to get there. We've offered it up in this report."

NASA released a response to the NRC's report. Here it is in full:

"NASA welcomes the release of this report. After a preliminary review, we are pleased to find the NRC's assessment and identification of compelling themes for human exploration are consistent with the bipartisan plan agreed to by Congress and the Administration in the NASA Authorization Act of 2010 and that we have been implementing ever since.

"There is a consensus that our horizon goal should be a human mission to Mars and the stepping stone and pathways thrust of the NRC report complements NASA's ongoing approach. The key elements of that approach include the facilitation of commercial access to low-Earth orbit to sustain fundamental human health research and technology demonstrations aboard the International Space Station (ISS); the development and evolution of the Space Launch System (SLS) and Orion spacecraft to enable human exploration missions in cis-lunar and deep space, including to an asteroid; and the development of game-changing technologies for tomorrow's missions, all leading the way on a path to Mars.

"NASA has made significant progress on many key elements that will be needed to reach Mars, and we continue on this path in collaboration with industry and other nations. We intend to thoroughly review the report and all of its recommendations."