Senior Chinese and Russian diplomats said dialogue should only resume based on "mutual respect" and all sanctions ought to be lifted.

China and Russia are both permanent members of the U.N. Security Council, along with France and Britain, that took part in the original 2015 Iran nuclear deal preliminary framework agreement. Trump withdrew America from the accord in 2018, setting in motion years of tensions in the wider Middle East.

President Trump said Russia, China and Iran may discuss "de-escalation" during upcoming nuclear talks in Beijing and suggested he might engage with North Korea on denuclearization.