ISTANBUL Türkiye is engaging with regional partners in ongoing negotiations over the use and development of natural gas resources in the Black Sea , amid rising geopolitical and economic interest in the Middle Corridor transport route, the head of the Black Sea Economic Cooperation (BSEC) group has said. The remarks came during the eighth International Blue Black Sea Congress, hosted by Marmara University in Istanbul on May 8–9. Speaking to state-run Anadolu Agency, Lazar Comanescu, secretary-