Which language has least number of letters?

Did you know : We all know English alphabet has 26 letters but do you know “Rotokas” alphabet has only 12 letters and they are A, E, G, I, K, O, P, R, S, T, U, V. Rotokas is known as the language with least number of letters. Rotokas is spoken by about 4,000 people on the island of Bougainville, Papa New Guinea. “Osireitoarei avukava iava ururupavira toupasiveira” is written in Rotokas, which means “The old woman’s eyes are shut”