Russia's last-minute demands in Iran nuclear talks risk upending negotiations altogether — and with it, the West's hopes of adding more Iranian oil exports to the tight oil market and mitigating Tehran's aggressive regional behavior. In a March 11 tweet, EU foreign policy chief Josep Borrell said the final text of a deal restoring compliance with the 2015 nuclear deal — formally known as the Joint Comprehensive Plan of Action (JCPOA) — was ''essentially ready,'' but that ongoing talks between global powers in Vienna to reach the agreement needed to be paused ''due to external factors,'' referring to Russia's recent push for sanctions relief. Over the last 10 days, Russian negotiators in Vienna have demanded Western governments guarantee the sanctions they've imposed related to the Ukraine invasion do not threaten Russia's economic, political and military relationship with Iran.