Ousted Malaysian Prime Minister Najib Razak says he had resigned as president of United Malay National Organisation (UMNO) party, and chairman of the Barisan Nasional alliance, with immediate effect.

Malaysia's veteran ex-leader Mahathir Mohamad, 92, won a shock election victory yesterday, in a political earthquake that toppled the country's scandal-plagued premier and ousted a regime that has ruled for over six decades.

Five Asian countries – Afghanistan, Pakistan, Cambodia, Malaysia and Thailand – are set to hold national elections this year.