WASHINGTON -- Lockheed Martin today revealed the industry partners on its bid to design America's next intercontinental ballistic missiles, as competitors Northrop Grumman and Boeing are staying silent on their teams.

John Karas, Lockheed Martin vice president and Ground Based Strategic Deterrent (GBSD) program manager, also revealed that the Air Force is open to bids that feature mobile control sites as part of the proposal.

The Lockheed GBSD offering teams the world's largest defense company with General Dynamics, which will focus on weapon system command and control; Draper Laboratories, which will help develop the guidance navigation and control systems; Moog, to provide the cross-vector control systems; and Bechtel, to help develop the launch facilities.

For the propulsion, Lockheed is working with both Aerojet Rocketdyne and Orbital ATK in order to find the best options for the engine. Karas said Lockheed is hoping to use "competition" to help drive down costs between the two companies.

He added that "probably late in the process" Lockheed plans to "select the right vendors for the right stages" but cautioned against calling it a down-selection. "I think it could be a mix of suppliers, it could be one supplier, it's just too early to tell."

Lockheed’s announcement stands in contrast to its two competitors for the program, both of which declined to name partners.

In a statement, Boeing spokesman Jerry Drelling confirmed that the company submitted its plan to the Air Force and notes that the company created the Minuteman ICBM in 1958. However, the company declined to reveal its partners.

Similarly, Northrop confirmed its participation in the competition but declined to name its partners.

"We are drawing on the expertise of the entire company for this capture," said Northrop spokeswoman Sally Koris. "In addition, we are leveraging industry partners with demonstrated performance in the design and development of ICBM systems.  We have built a team that has the ability to design and integrate all aspects of the weapon system."

The Air Force plans to award up to two 36-month technology-maturation and risk-reduction contracts by the end of fiscal year 2017. After down-selecting to a single bidder, it would then deploy the ballistic missile system in the late 2020s.

Interestingly, Karas said that Lockheed looked at both "fixed and mobile" command-and-control sites for the GBSD program.

"We traded off the [concept of operations] for mobile sites. I think the main driver is the survivability analysis, which was rather lengthy and complex, so we’re trying to provide the right blend of fixed sites and reduce the number of sites to help reduce the [operation and sustainment] costs but maintain all the survivability."

Karas declined to directly confirm whether the company came down in favor of mobile control sites or not, but emphasized that survivability analysis played a major role in its choices.

"It’s a very complex set of analysis. I do not believe the customer dictated whether you need to have so many fixed or so many mobile. Obviously, there is a set of trade-offs where you can add mobiles and reduce the number of fixed and vice versa," he said. "We had the opportunity to go bid mobiles if we wanted, and all that was in the trade space and we presented all that trade data in the proposal."