A Penang DAP delegate who caught flak for raising dissatisfaction over the party's alliance with former premier Dr Mahathir Mohamad at the annual general assembly has quit.

Taman Chai Leng DAP publicity secretary Shamser Singh Thind said he is resigning as he believes DAP is no longer a platform to fight against "corruption, racism and hypocrisy", after making amends with Mahathir.

"I have said and I am saying it again. Dr Mahathir is not interested in saving Malaysia. He has never admitted that his past actions and omissions were wrong," Shamser said in his resignation letter.

This comes as the late DAP chairperson Karpal Singh's daughter urges the party to ensure the principles of those it aligns itself to.

Speaking at the DAP national convention at Shah Alam today, Sangeet Kaur Deo said principles should not be sacrificed for political expendiency.

“I want to clarify at this stage that it was interesting to see Tun Mahathir in support of Maria’s release when it was him that was instrumental in the cruel enforcement of the Internal Security Act,” the USJ Subang Jaya brance delegate said.

“Now I strongly urge the leaders of DAP to be very mindful when we choose our allies. Yes, there are no permanent friends, there are no permanent enemies, but there must be permanent principles.

"And when we choose our allies, we must be sure that their principles are genuinely in line with ours,” The Malay Mail Online reported her as saying.

DAP secretary-general Lim Guan Eng had in his policy speech noted that there are no permanent foes in politics.

Mahathir had made an unexpected appearance at the convention today.

Both Sangeet and Guan Eng's fathers were detained under the ISA during Mahathir's tenure as prime minister.

Guan Eng's father is DAP veteran Lim Kit Siang.

Mahathir has not explicitly apologised but rebutted critics by sarcastically agreeing that he was a dictator because like all dictators, he resigned from his post.

Proponents of the alliance, however, say that if Kit Siang and PKR de facto leader Anwar Ibrahim who were incarcerated during the Mahathir era can bury the hatchet, then others should, too.

Having quit Umno over unhappiness with Umno president Najib Abdul Razak, Mahathir is now chairperson of Umno splinter party Parti Pribumi Bersatu Malaysia (Bersatu).