President Donald Trump is trying to preempt criticism by casting any agreement with Iran as the opposite of former President Barack Obama’s 2015 nuclear deal, even as some conservatives argue the emerging framework could follow a familiar playbook.

Iranian state TV has shared details from what it says is a draft "memorandum of understanding" with the US - but Washington has branded the report a "complete fabrication".

The sum Mr Trump has to contemplate – $24bn (£19bn), half of it to be paid upfront – would be released in exchange for a memorandum of understanding to end two similarly costly and politically painful...