Launches of U.S. military satellites will be opened to competitive commercial bids following criticism from both rivals and lawmakers of a joint venture between Lockheed Martin and Boeing that has dominated that launch market.

The U.S. Air Force has announced a proposal for bids to launch an intelligence satellite in 2 years, a process expected to set commercial space launch firm SpaceX against the United Launch Alliance LLC, a joint venture of Boeing and Lockheed Martin that has had a near monopoly on launches of military and intelligence satellites.

SpaceX founder Elon Musk had sued both the Pentagon and ULA in an effort to overturn the exclusive multiyear contract between them on sensitive satellite launching.

The Air Force announcement coincides with the Senate Appropriations defense subcommittee considering a spending measure that would give the Air Force $125 million to have another launch opportunity up for bid next year.

"Competition is a good thing and there is no competition in this to speak of," Sen. Richard Durbin (D-Ill.), the subcommittee's chairman, said during the markup hearing on the bill.

"The folks at SpaceX said 'we're ready to compete,'" Durbin said. "Let's give them the chance. Let's do it this next year. I think it's going to be interesting. I think it's going to reduce costs."

SpaceX, which has successfully accomplished a number of orbital launches in support of NASA missions, is predicted to win regulatory approval this year to conduct launches of smaller military payloads.

The California company is reportedly developing a larger rocket for satellite launching that would give it the resources to compete for all Pentagon contracts that become available.

Durbin expressed concern about the continued availability of the Russian-built engine used in one of ULA's main rockets, following increased tensions between the U.S. and Russia over the latter's military incursions into Ukraine.

"America's access to space should not depend on a state-owned foreign [company], which has dreams of empire at the cost of its innocent neighbors," Durbin said.

ULA has countered by saying it possesses enough engines on hand to continue launches for 2 1/2 years.

The Pentagon is said to be considering the development in the U.S. of a completely new engine to power military satellite launches.

The Obama administration has cautioned about rushing into such a development program that could take 8 years and cost U.S. taxpayers $4.5 billion.