NATO will significantly increase the number of forces on high alert to over 300,000 from 40,000 as part of the biggest overhaul of the alliance’s defences since the Cold War.
NATO Secretary General Jens Stoltenberg also confirmed that allies will expand troop deployments in NATO countries that sit closest to Russia.
The decisions will be set out at a landmark summit of the 30-member NATO alliance this week in Madrid, which is taking place in the shadow of Russia’s war in Ukraine.
“We will transform the NATO response force and increase the number of our high readiness forces to well over 300,000,” Mr Stoltenberg said.
The NATO Response Force is currently around 40,000 soldiers, sailors and air personnel.
Sky News revealed last week that it would be significantly increased, with two military sources saying that it would be six times the size.
The name is also set to be changed to the Allied Reaction Force, Sky News understands.
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Sky News was first to report the increase in forces last week before specific numbers were known.
Read more: The lessons the MoD is learning from Ukraine and what it means if the UK went to war with Russia
