He said it was the responsibility of Malaysia, China and Australia to see to it that the missing plane is found.
"We don't know what exactly happened in the cockpit so we don't know if it was a security issue or a safety issue. We have never had a situation where an aircraft flew for seven hours before crashing,” Benjamin said in an exclusive interview with The Straits Times newspaper.
Flight MH370 disappeared from radar screens about an hour after it left Kuala Lumpur for Beijing on March 8 last year, with 239 people on board.
Despite intensive search efforts in the Indian Ocean into which the plane is believed to have plunged, no physical trace of the Boeing 777 jet has been found.