Rice assessed Trump's move

"The last week has been a turning point. The best news we can give the Ukrainian people is that the United States and Europe have finally come to a consensus that Vladimir Putin cannot be stopped with words," the former US Secretary of State emphasized.

Condoleezza Rice believes that the Russian dictator can only be stopped if he is sure that he cannot go any further, that he cannot win.

The American diplomat's statement came after Donald Trump threatened that the US would impose "tough" sanctions against Russia if the Kremlin did not agree to a ceasefire within 50 days.

Against this backdrop, Rice also warned that the full imposition of secondary sanctions could be difficult due to Russia's key allies, China and India.

If you're China... with an economy that's not in the best shape... or India that really doesn't want to be on the losing end, you might wonder if it's really worth buying Russian oil at discounted prices.