Writing in the New York Times, the prime minister said “it is not future historians but the people of Ukraine who will be our judge”.
Mr Johnson set out a six-point plan, including rapidly strengthening defences in Nato countries.
But Labour criticised the PM for not acting more quickly over sanctions.
Ahead of a series of meetings with international leaders, the prime minister said: “Putin must fail and must be seen to fail in this act of aggression.
“It is not enough to express our support for the rules-based international order – we must defend it against a sustained attempt to rewrite the rules by military force.”
The invasion was condemned by 141 nations at the UN General Assembly this week while 39 countries, co-ordinated by the UK, made the largest-ever referral for war crimes to the International Criminal Court.
But Mr Johnson is set to call on world leaders to make a “renewed and concerted effort” to stop Russian President Vladimir Putin, Downing Street said.
In his six-point plan to maintain pressure on Mr Putin, the prime minister said:
- World leaders should mobilise an “international humanitarian coalition” for Ukraine
- They should also support Ukraine “in its efforts to provide for its own self-defence”
- Economic pressure on Russia should be ratcheted up
- The international community must resist Russia’s “creeping normalisation” of its actions in Ukraine
- Diplomatic resolutions to the war must be pursued, but only with the full participation of Ukraine’s legitimate government
- There should be a “rapid campaign to strengthen security and resilience” among Nato countries
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