The decision to drop Tan Sri Muhyiddin Yassin from the Cabinet was an extremely tough one, said Prime Minister Datuk Seri Najib Tun Razak.
He said the decision was necessary for the Cabinet to be united.
Muhyiddin was dropped as Deputy Prime Minister and Education Minister.
The Umno deputy president was replaced by Umno vice-president Datuk Seri Dr Ahmad Zahid Hamidi, who remained as Home Minister.
"I can accept difference of opinion but as a cabinet member one cannot do it in a public forum as it can create public misconception. This also affect the concept of collective responsibility," he said when announcing the new Cabinet line-up here on Tuesday.
Najib added that the reshuffle was also to strengthen the lineup before the 14th general election.
He said the decision to go ahead with the reshuffle took into account the political scenario and was in the best interest of the administration.
"This ensures that my administration remains committed and focused on development as promised by the Barisan Nasional government in the last general election," he said in his speech.
He added that the Cabinet should act as a team under all circumstances.