In a statement, Hishammuddin also promised that Malaysia "cannot and will not abandon" the families of the missing passengers, some of whom have sharply criticised the Malaysian government's handling of the mystery.
The Boeing 777 inexplicably disappeared en route from Kuala Lumpur to Beijing. No trace of it has been found despite an extensive Australian-led search effort deep in the Indian Ocean, where it is believed to have gone down.
Hishammuddin also offered Malaysia's thanks to Australia, China, the United States and fellow Southeast Asian countries for their assistance in the search.
Malaysian Airlines CEO Ahmad Jauhari Yahya issued a separate statement pledging similar resolve in finding the plane, calling the period since March 8 "the longest and most painful 100 days in Malaysia Airlines' history."
Anguished relatives of MH370 passengers have accused Malaysia's government of a bumbling and chaotic response to the crisis and covering up what happened to the plane.
Malaysia denies it is withholding information but has remained tight-lipped over investigations that it has launched into the mystery and given no timetable for when the findings of those probes will be released.