"One year after President Putin attacked Ukraine. It's clear that his war has been a strategic failure in every way," Blinken said in Athens at the close of a five-day trip to the region.

"No one wanted this war. No one likes this war. Everyone wants it to end as quickly as possible," Blinken said.

"If we allow this to go forward with impunity, then we will open a Pandora's box around the world where might makes right," he said.

Blinken's comments came as Putin delivered a state of the nation address in Moscow, blaming the West for the escalation of the Ukraine conflict and vowing to press on.

"Step by step, we will carefully and systematically solve the aims that face us," Putin said ahead of the first anniversary of the invasion.

Blinken on Friday attended the Munich Security Conference before flying to quake-stricken Turkey, where he announced $100 million in humanitarian aid.