Bangkok: Malaysia's 92-year-old former long-serving prime minster Mahathir Mohamad has been named to lead opposition parties into one of his country's most bitterly fought elections since independence.

Authorities in Kuala Lumpur have also announced that former popular opposition leader Anwar Ibrahim will be released from jail on June 8, opening the way for him to be possibly pardoned and eventually become prime minister.

Mahathir Mohamad, Malaysia's 92-year-old former prime minister. Credit:Bloomberg

Long-time arch enemies Mahathir and Anwar have come together in a stunning turnaround from years of bitter feuding that shaped Malaysia's political landscape for almost two decades.

The pair are seen as the biggest threat for Prime Minister Najib Razak, who is engulfed in a multi-billion dollar corruption scandal.