America has deployed weapons in space to guard against "hostile adversary action", the US military confirmed for the first time.
In the most direct acknowledgement so far, the US air force secretary said it already has space weapons in place above the Earth.
Troy Meink confirmed the move in a speech at the Air, Space & Cyber Conference in Maryland on Monday.
He didn't state which weapon was deployed, whether it had been tested, or how many there were.
However, he said the Space Force had "on-orbit space control weapons capable of defending the joint force against hostile adversary action".
Mr Meink said it was "critically important that we maintain our dominance, not only in the air but in space", reported Air & Space Forces Magazine.
"We've had to take steps to make sure that when we're threatened, we can take care of that," he added.
Donald Trump last year announced plans for a "Golden Dome" missile defence system including both ground systems and "space-based sensors and interceptors".
The president said it would allow missiles to be intercepted "even if they are launched from the other side of the world".
The Pentagon has warned updated measures are needed to counter the latest hypersonic and intercontinental ballistic missiles (ICBMs) developed by Russia and China.
Elements of the plan include the capability to shoot down ICBMs in the 'boost phase' as they take-off, before they leave the Earth's atmosphere and travel towards their target.
Partly inspired by Israel's Iron Dome system, President Trump said he wanted Golden Dome operational by the end of his second term in 2029.
In April, Space X and defence giants Lockheed Martin and Northrop Grumman were among 12 firms given contracts to produce concepts for space-based interceptor systems.
Dr Mark Hilborne, senior lecturer in defence studies at King's College London, told Sky News the US had been designing and testing such weapons since about 2023.
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He said a 1967 international treaty banned weapons of mass destruction in space but didn't "explicitly ban any other types of weapons".
He said the weapon already deployed by the US probably had capabilities such as "electronic jamming, electronic warfare" - or could simply be a satellite that could collide with another.
"I think on the back of this announcement we might find that China or Russia reveal some other capabilities or start building some capabilities," he added.
(c) Sky News 2026: US confirms it has deployed weapons in space to counter 'hostile' enemy action
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