China and Russia will.
“China and Russia will.” (go to the mat for Iran)
Russia stood down its air defenses in Syria, and allowed Israel to attack Iranians there, in recent weeks.
China, in recent weeks, promised to prevent further sanctions busting against Iran by its companies, to save their electronics company ZTE. Neither has sided with Iran in any substantive way - just some conciliatory statements, and small scale smuggling.
Russia has had some talks about using cryptocurrency, for the Iranian elite to smuggle some of their money out of the country, but nothing that is going to run them afoul of US sanctions (that is, nothing that will prop up the regime long term).