The Turkish Embassy has issued a clarification of new rules for passage of ships through the Turkish straits, saying that only ships carrying dangerous cargo, including oil, are required to give advance warning of their approach. Only large Turkish ships, not foreign vessels, are required to use pilots to go through the straits, Ahmet Erozan, the embassy's first counsellor, said Tuesday.The embassy previously said that ships passing through the Bosphorus and Dardanelles should give advance warning and could be assigned pilots if they carried dangerous cargo.Russia last week announced it would ignore obligatory assignment of pilots and protested other new rules as well. An official at the Foreign Ministry insisted that the new rules could be interpreted by Turkey to force Russian ships to accept pilots.