(ANSA) - BELGRADE, JUL 8 - Turkey, Romania, and Bulgaria have signed an amendment to the memorandum of understanding that governs the trilateral mine countermeasures task force in the Black Sea, expanding the group's mandate to include the protection of critical underwater infrastructure. The three countries' defence ministers signed the agreement in Ankara during a meeting on the sidelines of the NATO summit, according to Anadolu Agency. (ANSA).