And now on Tuesday Secretary of State Mike Pompeo is vowing to never let Iran acquire Chinese and Russian weapons, but it remains unclear precisely how he hopes to make this happen. 

Pompeo said during an interview with European radio broadcaster "France Inter" on Tuesday that "Nothing has been done so far to enable the extension of this ban, and therefore the United States assumed its responsibilities." He's of course referencing the fact that the Europeans have by and large sought to uphold the terms of the 2015 nuclear deal, or JCPOA.

Pompeo added: 

"We will act in this manner. We will prevent Iran from acquiring Chinese tanks and Russian air defense systems, and after that, selling weapons to Hezbollah undermines the efforts of French President Emmanuel Macron in Lebanon."

Washington has stood isolated over its decision to enact so-called "snapback" sanctions on the Islamic Republic in late August. 

Ironically the snapback option is available to participants in the JCPOA, which the US formally withdrew from in May 2018.