MADRID, JUNE 27

NATO will increase the number of its forces at high readiness massively to over 300,000, Secretary-General Jens Stoltenberg said on Monday.

"We will transform the NATO response force and increase the number of our high readiness forces to well over 300,000," he told reporters ahead of a NATO summit in Madrid later this week in Madrid.

NATO's quick reaction force, the NATO response force, so far has some 40,000 troops.

At the Madrid summit, NATO will also change its language on Russia that in the alliance's last strategy from 2010 was still described as a strategic partner.

"That will not be the case in the strategic concept that we will agree in Madrid," Stoltenberg said.

"I expect that allies will state clearly that Russia poses a direct threat to our security, to our values, to the rules-based international order."