Natalya Timakova also told journalists that the president had ordered Emergency Situations Minister Sergei Shoigu to do everything necessary to ensure the bodies of the dead Russians are brought home, and that the survivors receive all the assistance they need.
Vietnamese media reported that 15 people had died in the accident, which happened around 7 p.m. local time (12:00 GMT) on Friday. The Russian Embassy in Vietnam earlier confirmed that nine Russians had been killed.
The tour group's Vietnamese guide was also killed when the bus fell down a precipice about 50 kilometers from the tourist city of Dalat as the bus carrying 24 tourists returned from a day trip.
The Vietnamese driver of the bus was among the injured. The cause of the accident is being investigated.
Similar tragedies involving Russian tour groups occurred last December in Israel and Egypt. On December 16, 2008, 24 Russians died in a bus crash near the Israeli Red Sea resort city of Eilat and six days later another seven Russians died near Dahab on Egypt's Sinai Peninsula.