President Donald Trump has finally found a way to like arming Ukraine: ask European allies to donate their weapons, and sell them American replacements.

Vladimir Putin’s conduct has prompted Donald Trump’s shift as Russia’s war effort in Ukraine has gotten only more aggressive.

After European leaders stepped up military spending, President Trump aligned himself more closely with them on the war. But his tariff threats have left bruises.

The change in Trump’s approach may also mean that the $US8 billion (£6 billion) of frozen Russian assets in the US (and US$223 billion in Europe) could be released to aid Ukraine, which would provide a ready means to pay for the US arms transfers.

To appreciate the dramatic shift in President Donald Trump’s policy towards Ukraine, consider two scenes in the Oval Office, months apart:

President Trump is applying pressure on Moscow by restoring weapons pipelines to Ukraine and imposing tariffs on Russia's trading partners, in an effort to weaken Russia's war economy and prevent further Russian gains in Ukraine.

While Trump's new Russia policy announcement was welcomed by and large, there are still challenges ahead that will require more from America.

After years pressing to end U.S. aid to Ukraine, many Republicans have abandoned that position now that President Trump is supporting the country against Russian aggression.

President Donald Trump's ultimatum to Russia to accept a peace deal in Ukraine within 50 days or face bruising sanctions on its energy exports has given the Kremlin extra time to pursue its summer offensive.