Nato is planning to include space as an official domain of warfare this year, according to reports, as the multinational body bids to show a sceptical President Donald Trump that it is still relevant.
Four senior diplomats told Reuters that the decision would be made at a December summit in London, which Mr Trump is due to attend.
The new policy will formally acknowledge that battles can be waged not only on land, in the air, at sea and on computer networks, but also in space.
"There's agreement that we should make space a domain and the London summit is the best place to make it official," said one senior Nato diplomat involved in the discussions, although cautioning that technical policy work was still underway.
Nato diplomats deny the alliance would be on a war footing in space, but say declaring it a domain would begin a debate over whether Nato should eventually use space weapons that can shut down enemy missiles and air defences or destroy satellites.
Nato currently owns 65 per cent of satellite in space, but China has ambitious plans for commercial satellites that can offer services ranging from high-speed internet for aircraft to tracking missiles and armed forces on the ground.
Recognising space as a domain of warfare would perhaps convince Mr Trump that Nato has a valuable role in deterring China's rise as a military power, the diplomats hope.
Russia, once a strategic partner for Nato but now viewed by many allies as a hostile power, is also a force in space and is one of the few countries able to launch satellites into orbit.
"You can have warfare exclusively in space, but whoever controls space also controls what happens on land, on the sea and in the air," said Jamie Shea, a former Nato official and now an analyst at Friends of Europe think-tank in Brussels.
"If you don't control space, you don't control the other domains either."
Nato defence ministers are expected to agree to a broad space policy next week at a regular meeting in Brussels, although there will be no decision yet to declare space an operational domain of defence.
A second diplomat said that while the decision was weighty and had real consequences, it would likely be "a gift to Trump".
Mr Trump signed a plan in February to create a US Space Force, and the phrase "space force!" has become as popular a rallying cry among his followers as "build the wall".
Mr Trump used the last Nato summit, in July, to harangue European allies over defence spending and accused Germany of being a prisoner of Russian energy.
The diplomats hope that the announcement will stave off some of Mr Trump's anti-Nato ire.
Most sensitive of all would be deciding if an attack on an allied satellite constituted an assault on the alliance and whether to trigger Nato's Article 5 collective defence clause.