Will US sanctions squeeze Russia’s war machine? Plus: The art genius of Gerhard Richter

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Donald Trump’s sudden decision last week to sanction Russian oil producers suggested the US president has finally lost patience with Vladimir Putin after a series of fruitless talks over ending the war in Ukraine.

Could it break the deadlock? Oil sanctions have the potential to genuinely damage Moscow’s finances, as the Russian president himself admitted last week. It remains to be seen, though, whether economic pressure alone can bend Putin’s arm over a conflict he views as defining to his legacy.