Kuala Lumpur  - Malaysia's king appointed Najib Razak as the country's new prime minister Friday in a solemn swearing-in ceremony held at the royal palace.

Dressed in black traditional Malay clothing Najib took his oath of office, loyalty and confidentiality before King Mizan Zainal Abidin, making him the country's sixth prime minister.

"I pledge to fulfil the requirements of my role with honesty, and with my fullest abilities," said Najib, witnessed by an audience which included cabinet members as well as his predecessor Abdullah Ahmad Badawi.

Najib, the eldest son of Malaysia's second prime minister, also pledged to "keep, protect and defend the constitution."

Abdullah had submitted his letter of resignation Thursday after five years in power. (dpa)