The total financing required for the Oyu-Tolgoi underground mining development, known as OT Phase 2, is USD 16 billion. USD 4.2 billion has already been secured from 15 interrnational commercial banks. The officials are saying that the financing issue is now almost solved completely.  Oyu-Tolgoi can then start work on the underground mine in earnest. Rio-Tinto plans to sign the financing contract for Phase 2 next Wednesday, in Ulaanbaatar.