Minister in the Prime Minister's Department Abdul Rahman Dahlan described Pakatan Harapan's decision today to officially name Bersatu chairperson Dr Mahathir Mohamad as its prime ministerial candidate as a "shame and tragedy".

"Finally Harapan chose someone they called the most corrupted man in Malaysia as their prime minister (candidate). What a shame.

"The announcement of Mahathir as PM (candidate) is a gross disservice to Harapan's own reform agenda. It's a tragedy to their own cause," Abdul Rahman said in a series of posts on Twitter.

Abdul Rahman also mocked Harapan for announcing a slew of reforms together with the naming of Mahathir as the prime ministerial candidate.

"The truth is Mahathir won’t implement those reforms. He has been proven to be master of deceits and useless reformer," he said.

"It’s laughable for Harapan to appoint Mahathir as the next PM and expect him to implement those reforms," he said.

Abdul Rahman also questioned if Harapan had sacrificed its ideals in its quest for power.

"Bottom line is Mahathir is not synonymous with the reform initiatives concurrently announced by Harapan today. Bad, bad strategic move," said the BN strategic communications director in a series of tweets.

Ultimately, Abdul Rahman claimed the move will benefit BN.

"The announcement of Mahathir as their PM candidate is absolutely good news for BN. Harapan shows how all these years of talking about reform and giving the young people a chance were mere rhetoric," he said.

Among the reform pledges announced today included a two-term limit on the prime minister.

The coalition will also require all top positions in the country such as the attorney-general, inspector-general of police, armed forces chief, MACC chief, Election Commission chief and auditor-general to undergo a parliamentary confirmation hearing before they are appointed by the Yang Di-Pertuan Agong.

This is on top of its often touted institutional, economic and social reforms as well as promises to abolish the Goods and Services Tax, stabilise fuel prices and uphold the Malaysia Agreement 1963.