Speaking after US President Donald Trump signed the measures, Jean-Claude Juncker said the EU would take counter measures if the US sanctions harmed European companies involved in oil and gas projects with Russia. This was reported by Reuters.
"We are ready: we must defend our economic interests vis a vis the United States, and we will do that," Juncker said, according to a transcript provided by his press team.
The US measures, approved by Trump despite his desire to improve relations with Moscow, have angered EU officials, who see them as breaking transatlantic unity in the West's response to Moscow's annexation of Ukraine's Crimea region in 2014 and support for separatists in the east.
Juncker said station that it was crucial to coordinate with the United States to ensure sanctions against Russia over its role in the Ukraine crisis are effective.
As it was reported earlier German Economy Minister Brigitte Zypries said the sanctions could hit European firms involved in the construction, operation and maintenance of natural gas pipelines from Russia, an extra-territorial impact that Europe could not accept.