Iran's Supreme Leader Ayatollah Ali Khamenei called a trade mechanism launched by European countries to bypass renewed US sanctions a “bitter joke” on Thursday, in a speech aired by state TV.

“This financial channel they recently set up resembles a joke, a bitter joke,” Khamenei told a thousands-strong congregation at a shrine in the northeastern city of Mashhad, where he speaks every year to mark Iranian new year.

Britain, France and Germany launched the special payment system, called INSTEX — the Instrument in Support of Trade Exchanges — in late January after President Donald Trump abruptly quit the 2015 nuclear deal between Iran and world powers in May last year.

The three countries were the European signatories to the deal, also signed by the US, Russia and China, that curbed Tehran's nuclear ambitions in return for sanctions relief.

London, Paris and Berlin launched the device in the hope it will help save the deal by allowing Tehran to keep trading with European companies despite Washington reimposing sanctions.

Take a look: What is the Iran atomic deal and why is it being targeted?

“The difference between what they are obligated to do and what they are proposing is as far as the earth is from the sky,” Khamenei said.

“We should completely forego (any hope) of help or cooperation from westerners in strengthening our economy, we shouldn't wait for them,” he added, calling western politicians “savages”.

“Once again the Europeans have stabbed us in the back, they have betrayed us,” Khamenei said.