Dr Mahathir Mohamad is forced to woo the Chinese community through DAP after failing to garner support within Umno, said Prime Minister Najib Abdul Razak’s press aide.

Tengku Sarifuddin Tengku Ahmad claimed that Umno rejected Mahathir because he wanted to topple the current prime minister to engineer the political ascension of his son Mukhriz.

"This is why Mahathir has lost the support of Umno.

"Which in turn is why he had to leave Umno and solicit Chinese support from the opposition through (DAP veteran) Lim Kit Siang, a man he previously jailed," he added in a statement.

Tengku Sarifuddin also accused Mahathir of fabricating allegations against Najib which he claimed turned off Umno members.

"Damaging the national interest just to benefit your son, such as Mahathir's lie that RM42 billion was missing from 1MDB, is also a step too far for Umno.

"The Public Accounts Committee's (PAC) report proved that Mahathir's attack on the prime minister using 1MDB is like thunder with no lightning," he said.

Tengku Sarifuddin reiterated that if Mahathir was not out to install his own son as the new prime minister, he should name his candidate for the top post.

"How can a man who wants to dictate and decide everything avoid answering this one critical question?

"Until he does, Mahathir cannot blame the people for believing that his failed attempt to unseat the prime minister is all about paving the way for his son," he said.

Tengku Sarifuddin claimed that Mahathir had for years tried to prop up his son but blamed Najib when Mukhriz was unsuccessful.

"Firstly, Mahathir made his son stand for Umno vice-president but he was defeated due to a lack of support by party members, and his father blamed the prime minister.‎

"Then, Mukhriz stood as menteri besar of Kedah, Mahathir’s home state and power base but he was removed due to a lack of support by party members, and again his father blamed the prime minister.

"If Mukhriz had 80 percent support within Umno as he claims, he would be vice-president of Umno or menteri besar of Kedah," he said.

Tengku Sarifuddin said Najib will continue to focus on key issues that matter to Malaysia, particularly on the threat of terrorism and the economy.