NATO "is a defensive alliance. We seek no conflict. But if the conflict comes to us, we are ready for it," Blinken told reporters while on his way to an extraordinary meeting in Brussels among top diplomats in the alliance.
With the latest developments in the war between Russia and Ukraine, as well as the alliance's response to it, at the top of the meeting's agenda, Blinken also vowed that NATO would defend "every inch" of its territory.
In a doorstep speech, NATO Secretary-General Jens Stoltenberg condemned "the brutal Russian invasion of Ukraine" and attacks against civilians.
He pointed out that the latest reports on Russian troops attacking the Zaporizhzhia nuclear plant in southeastern Ukraine "demonstrates recklessness of this war."
Stoltenberg also repeated NATO's call on Russia to withdraw all its troops and engage in diplomatic talks.
The foreign ministers of Sweden and Finland, as well as top EU diplomat Josep Borrell, are also taking part in the meeting.
Last week, NATO decided to activate its defense plans enabling it to deploy capabilities and forces more easily in NATO territory.
