Russia's state media say an estimated 3,700 tons of low-grade fuel oil has spilled into the Kerch Strait after two Russian ships were seriously damaged by stormy weather.

A heavy storm Sunday damaged two Russian tankers carrying thousands of barrels of oil and caused an unknown amount to spill into the sea, according to reports from Reuters.

Russian oil tankers began sinking near the Kerch Strait on December 15. They set out to sea without complying with navigation requirements, the Ukrainian media Suspilne reports, citing Dmytro Pletenchuk,