DAP candidate for the Teluk Intan parliamentary by-election Dyana Sofya Mohd Daud should have a deeper understanding of the DAP relentless struggle to champion secularism, said an UMNO stalwart.

Johor Baharu UMNO division chief Tan Sri Shahrir Abdul Samad said he was shocked over Dyana Sofya's statement that she would toe the party's line by opposing the PAS sponsored Hudud Bill in Parliament if she were to win the by-election.

He said secularism was the principle of the separation of government institutions and persons mandated to represent the state from religions and religious institutions.

"Is it possible for the DAP to have a party line since it is a secular party?" he posed the question at a news conference here Wednesday.

As the DAP upholds secularism, he said it should allow Muslim leaders and elected representatives in the party to make a stand as Muslims.

Shahrir said personally, he respected Dyana Sofya's political conviction although she grew up in a family that had been supporting UMNO.

"The situation now is more open where no one should be surprised if his or her family members were to have different political views just like my siblings and I.

"My older sister was influenced by socialism while studying in UK in the 60s.

"On the other hand, I'd got acquainted with UMNO that pursued the New Economic Policy while studying at University of Malaya while my younger brother (Shah Alam MP Khalid Abdul Samad) supported PAS as he was influenced by the Islamic Revolution while studying in the UK," said Shahrir.

On the by-election, Shahrir said he was confident that Barisan Nasional (BN) would recapture the seat as its candidate, Datuk Mah Siew Keong had been serving the constituency despite losing the seat in the last two general elections.

Mah, who is also Gerakan chairman, was two-term Teluk Intan MP but lost in the contest for the seat in 2008 and 2013.