An Umno Youth leader has accused Dr Mahathir Mohamad of embracing DAP after failing to use Umno as a launchpad for his son Mukhriz to become prime minister.

Khairul Azwan Harun also suggested that there could be fireworks if DAP disagreed to endorse Mukhriz for the top post.

The Umno Youth vice-chief claimed that when Prime Minister Najib Abdul Razak refused to cave in to pressure with regard to Mukhriz, Mahathir plotted to topple the prime minister.

"However, this attempt was thwarted. The Umno leadership and grassroots chose to reject Mahathir's political agenda, and prioritised the interests of the people and Umno instead.

"After failing to use Umno for this purpose, Mahathir was willing to do anything, including forming an alliance with DAP.

"Najib is now the target of intense criticism for refusing to be Mahathir's political hostage," said the newly-minted senator in a media statement.

Khairul also suggested that the Mahathir-DAP alliance based on political interests might not have a long shelf life.

DAP has always endorsed jailed opposition leader Anwar Ibrahim for the prime minister's position.

In May, Mukhriz sued Najib's press secretary Tengku Sariffuddin Tengku Ahmad for defamation, claiming the latter had alleged that Mukhriz was conspiring with his father and former deputy prime minister Muhyiddin Yassin to topple the lawful government.

Mukhriz claimed Tengku Sariffuddin suggested that he would be given the prime minister's post once Muhyiddin steps down after replacing Najib as prime minister.

Meanwhile, Bersatu Youth chief Syed Saddiq Abdul Rahman dismissed claims that Mukhriz was out to become prime minister, accusing Khairul of being the one who was made for power.

"If Mahathir had wanted to move Mukhriz up, he could have done it when he was prime minister for 22 years but he banned his children from having any major role in Umno while he was in power.

"It is Khairul who was opportunistic and abandoned his principles to be appointed as a senator by Najib," Syed Saddiq said in a statement today.

He said while Mukhriz was fighting for the rakyat, Khairul had turned a blind eye to the prime minister's alleged wrongdoings.

Najib has denied any wrongdoing or taking public funds for personal gain.