A Liberal candidate who linked same-sex marriage and paedophilia will not be dumped by the party, the Prime Minister has declared.

Key points: Gurpal Singh was a 'No' campaigner ahead of the 2017 same-sex marriage plebiscite

Gurpal Singh was a 'No' campaigner ahead of the 2017 same-sex marriage plebiscite Scott Morrison says the comments linking same-sex marriage to paedophilia have been dealt with by the organisation

Scott Morrison says the comments linking same-sex marriage to paedophilia have been dealt with by the organisation Three Liberal candidates, two Labor candidates and a Greens candidates have been disendorsed during the election campaign over controversial or extremist views

Gurpal Singh was a 'No' campaigner ahead of the 2017 same-sex marriage plebiscite, where he argued against gay adoption and surrogacy.

"I think it is also an issue of paedophilia," Mr Singh told SBS Radio.

"In these situations, the occurrence can be high."

In the interview, the lawyer also said there would be "very serious" implications for children raised by a same-sex couples.

"When they grow up, how they will reconcile to the situation is beyond comprehension."

Scott Morrison last week appeared to lay down a series of rules for dealing with controversial and extremist candidates.

"The standard you walk by is the standard you accept," Mr Morrison said while attacking then-Labor candidate for Melbourne Luke Creasey.

"The issue is not whether he's contrite, it's whether that's a standard that Bill Shorten is prepared to accept."

Mr Morrison last Wednesday lost one candidate over an anti-Islamic rant, along with another caught wanting to prevent Liberal "homosexual MP" Tim Wilson gaining preselection.

"These individuals we identified … need to be dealt with swiftly and appropriately," he said a week ago.

In a brief exchange at today's media conference, the Prime Minister distanced himself from Mr Singh's comments but confirmed his candidacy was secure.

Journalist: You've got a candidate in Scullin who in an interview in 2017 linked paedophilia with same-sex marriage. Do you and the Liberal Party accept those comments from him? PM: That matter was dealt with by the party organisation several weeks ago, the party organisation dealt with it. Journalist: What did they do to deal with it, Prime Minister? If you said they dealt with it, what did they do? PM: His candidacy has continued. Journalist: If he's still in the job though that means you think that those comments are acceptable? PM: No, I don't accept that.

The political hopeful is running for the safe Labor-held seat of Scullin in Melbourne's northern suburbs.

The electorate voted 53 per cent to 47 in favour of legalising same-sex marriage.

Mr Singh recently withdrew his remarks.

"I apologise unreservedly for those comments. They were wrong, and I am sorry," he said when approached by Nine newspapers.

Labor senator Kristina Keneally said the Prime Minister had "failed to show any leadership" on the issue.

In the 2017 interview, Mr Singh also slammed the Coalition for holding a multi-million-dollar public vote on same-sex marriage.

"The Turnbull government is weak, it is their responsibility to legislate on these issues, but they have thrown it onto the people," he told SBS.

The Liberal Party last week also lost Tasmanian candidate Jessica Whelan over anti-Islamic posts.

The ALP disendorsed Senate candidate Wayne Kurnorth over online posts which included a conspiracy suggesting the world was being run by a society of Jewish shapeshifting lizards.

The Greens dropped their candidate for the Melbourne seat of Lalor today over distasteful posts on Facebook, in which he joked about having sex with dead people and made a racist joke about an Asian friend.