Donald Trump estimates his high-stakes diplomatic talks with Russia's Vladimir Putin have a 25% chance of failure. 

The two presidents will meet in Alaska tomorrow to discuss an end to the war in Ukraine.  

Trump's previewed the summit as setting the table for a second meeting, inviting in Ukraine's Volodymyr Zelensky.  

New Haven University international affairs expert Matthew Schmidt told Mike Hosking public opinion in Ukraine is strong, on a need to stop the bleeding.  

But he says they're not willing to give away everything or be humiliated to get there, so Trump will have to navigate that.  

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