WASHINGTON — The secretary of the U.S. Air Force said Thursday he’s not concerned about Russia’s decision to cut off the United States’ access to more RD-180 rocket engines.

“I have not been informed at this point of any major launch concerns associated with that,” Frank Kendall told reporters during a media roundtable at the Air Force Association’s Air Warfare Symposium.

The head of Roscosmos, Russia’s space agency, said Thursday the country would no longer sell the RD-180 to the U.S. or provide support for launches powered by the Russian-made engine.

“In a situation like this we can’t supply the United States with our world’s best rocket engines,” Dmitry Rogozin said in an appearance on Russian state television, Reuters reported. “Let them fly on something else, their broomsticks, I don’t know what.”

The United Launch Alliance — one of two launch providers certified to fly national security space launches — carries the RD-180 on its Atlas V rocket, which the company is set to retire in 2025. The company has said it has enough engines on hand to power the remaining scheduled Atlas V launches.

Asked to respond to Rogozin’s threats, which began on Twitter earlier this week, ULA CEO Tory Bruno said the company has “developed considerable experience and expertise” to troubleshoot any unexpected engine issues without help from Russia.

The United States has in recent years weaned itself from the RD-180, developing an assured access to space strategy to invest in domestic launch vehicle suppliers and ensure at least two companies are certified to launch national security space payloads. The new strategy was driven by a 2016 congressional directive to eliminate reliance on the Russian-made propulsion system by 2022.

Since then, the Air Force has introduced competition into its space launch program, certifying military space launch newcomer SpaceX to fly national security missions and awarding the company, along with long-time provider ULA, a five-year contract for launch services through fiscal 2027. The service has also invested in domestic launch vehicle development, providing early funding for ULA’s Atlas V replacement, the Vulcan Centaur.

Despite some recent schedule setbacks, ULA plans to fly Vulcan for the first time this year.

Kendall noted that the purpose of DoD’s strategy — which he played a significant role in crafting in his former role as Pentagon acquisition chief — was to eliminate dependencies on Russia.

“The whole point of the program we put in place several years ago was to work our way off of the RD-180,” he said. “Other suppliers like SpaceX, for example, have come on board. ULA is moving towards a different solution that doesn’t involve the [RD-180]. I think our launch needs will be met.”

Courtney Albon is C4ISRNET’s space and emerging technology reporter. She has covered the U.S. military since 2012, with a focus on the Air Force and Space Force. She has reported on some of the Defense Department’s most significant acquisition, budget and policy challenges.