The refinery, which delivers oil products mainly for exports, had stopped operations from April 16 after a drone attack, industry sources have said.
Ukraine has ramped up its strikes on Russia since March as the US-brokered peace talks have been paused with Washington mainly focusing on the war in Iran.
The Tuapse refinery has annual production capacity of about 12 million metric tonnes, or 240,000 barrels per day, turning out naphtha, diesel, fuel oil and vacuum gasoil.
Since the start of its offensive in Ukraine in February 2022, Russia has been regularly bombing Ukraine, especially key infrastructure sites.
In response, Kiev has struck targets in Russia, insisting it is aiming at military sites as well as energy facilities in order to reduce Moscow’s ability to finance its war effort.
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