The North Atlantic Treaty Organisation plans to widen its remit to include outer space as the alliance anticipates new security threats.
Nato intends to make space an “operational domain” along with air, land, sea and cyber, Secretary General Jens Stoltenberg said.
The move, to be approved at a meeting of Nato foreign ministers on Wednesday, would bring all five areas within the scope of the alliance’s collective-defence commitment and comes as member countries try to address internal splits.
“Space is of great importance for our civilian societies and for any military operation,” Mr Stoltenberg said on Tuesday in Brussels.
“It’s about communications, it’s about navigation, it’s about data imagery. Space is essential for almost everything we do.”
Nato is seeking to adapt to new external challenges as its leaders prepare to meet in London on December 3 and 4, to mark the 70th anniversary of the alliance's founding.
Already shaken by US President Donald Trump’s demands for European allies to spend more on defence, the 29-member alliance is grappling with internal political tension over a Turkish incursion into northern Syria last month to challenge Kurdish forces.
Turkey, which has Nato’s second-biggest army after the US, received Mr Trump’s approval for the military operation that European countries including France and Germany oppose.
That prompted French President Emmanuel Macron to say a lack of strategic co-operation among Nato members showed the alliance was suffering a “brain death” in a remark that irritated many countries in the US-dominated alliance.
“We firmly disagree with President Macron’s assessment,” the US ambassador to Nato, Kay Bailey Hutchison, said on Tuesday in Brussels.
“Nato is absolutely essential if we are going to assess the risks that we face altogether.”
Mr Stoltenberg said he would travel to Paris next week for talks with Mr Macron, who has pushed for greater European influence in the bloc's defence policy.
Mr Stoltenberg echoed German arguments that European military initiatives must complement Nato, rather than compete with it.
“We need more European efforts on defence but not as an alternative, not as something that is replacing Nato,” he said.
Mr Stoltenberg called Nato’s plan to integrate space into the alliance’s operations a “defensive” step, saying it would be a “clear sign that we continue to strengthen our deterrence and defence".
Mr Stoltenberg said Nato had no intention of putting weapons in space.