Democratic US Senator Bernie Sanders from Vermont introduced legislation on Monday to prevent the use of federal funds for any "illegal wars” in or against Iran without approval from Congress.

Sanders introduced the “No War Against Iran Act”, which contains an exception for self-defence as enshrined in the War Powers Act and applicable US law.

“It is imperative that we make clear that the President has no authority to embark on another costly war without explicit authorization by Congress,” Sanders said in a statement on Monday.