President Vladimir Putin and his Turkish counterpart Recep Tayyip Erdogan met in Istanbul to inaugurate TurkStream pipeline in a ceremony celebrating the nations’ energy and political ties. TurkStream is set to carry Russian gas under the Black Sea to Turkey and supply several countries in southeastern Europe once fully operational, just as U.S. sanctions stall another Gazprom PJSC export line, according to Bloomberg.

TurkStream consists of two pipelines running together underwater, each with an annual capacity of 15.75 billion cubic meters. Gas via the link has been flowing to Turkey and Bulgaria since Jan. 1, according to utility Bulgargaz. A combination of existing and new pipelines will subsequently take supplies to Serbia and later on to Hungary.