The European Union's latest effort to restrict Russia's oil revenue is unlikely to hurt Moscow's war effort severely, leaving U.S. President Donald Trump's threat of secondary sanctions one of the few remaining economic levers to pressure the Kremlin.

Last week, the European Union announced its 18th sanctions package against Russia, something that could have an impact on the oil industry both abroad and in the Lone Star State.

The European Union has sanctioned two small Chinese banks in its latest package of measures designed to hobble Russia’s war machine, despite a warning from Beijing to expect consequences. Suifenhe Rural Commercial Bank and Heihe Rural Commercial Bank,