WASHINGTON -- US President Donald Trump on Tuesday morning slammed key European allies, accusing France of declining to allow military supply flights to Israel to cross its airspace and faulting Britain for refusing to take part in the US-Israeli war with Iran.

"The Country of France wouldn't let planes headed to Israel, loaded up with military supplies, fly over French territory," Trump said in a post on his social platform Truth Social, describing the major European country as "very unhelpful."

In an earlier post, Trump said that Britain, one of the United States' closest allies since WWII, "refused to get involved in the decapitation of Iran," urging Britain and other countries affected by fuel shortages due to the closure of the Strait of Hormuz, a critical artery for global oil and fuel flows, to buy oil from the United States or "go to the (Hormuz) Strait, and just take it."

"You'll have to start learning how to fight for yourself, the USA. won't be there to help you anymore, just like you weren't there for us," Trump said. "Go get your own oil!"

Trump suggested the US allies should now take greater responsibility for securing energy supplies and trade routes and rely less on US military support since Washington had already borne the burden of the conflict, arguing that Iran had been "essentially decimated."

Trump's remarks marked a further escalation in tensions between Washington and its European allies over the US-Israeli war with Iran, raising questions about future coordination of the Transatlantic alliance on maritime security and regional stability.

European governments have been cautious about military involvement in Iran. Days after the United States and Israel launched massive attacks on Iran on Feb 28, Kaja Kallas, the European Union's (EU's) top diplomat, said: "This is not Europe's war, but Europe's interests are directly at stake."

Ongoing tension in the Middle East, which has now entered its fifth week with no clear resolution in sight, has led to a sharp increase in energy prices. Euro area annual inflation is expected to rise to 2.5 percent in March from 1.9 percent in February, driven by a steep rise in energy prices, which climbed to 4.9 percent from -3.1 percent, according to a flash estimate published by Eurostat, the statistical office of the European Union on Tuesday.