Richard McGilvray resigned hours after the senator for Queensland delivered his first upper house speech on Tuesday night.

McGilvray, who managed the senator’s legislative agenda and negotiations with stakeholders, said he could not condone the views expressed in the speech.

“His reference to ‘The Final Solution’ was not something I had seen, heard of, or discussed prior to his remarks last night,” McGilvray posted on LinkedIn.

“As a consequence, within hours of Senator Anning’s speech, I resigned my position effective immediately.”

McGilvray thanked people for their messages of support and encouragement.

Despite copping criticism from all sides of politics as well as religious and migrant groups, Anning has refused to apologise and does not regret anything he said in the speech.

Home Affairs Minister Peter Dutton said the Katter’s Australian Party senator was wrong not to apologise after claiming he didn’t make the connection between “the final solution” and the Holocaust.

“If he says he’s made a mistake then apologises and people can make their own judgments about that,” Dutton told Sydney radio 2GB.

“But to keep your hands in your pockets and hold the ground, I just think he’s making a mistake, but ultimately that’s a judgment for him.”

Anning is continuing his call for a plebiscite on “European immigration” despite ferocious criticism of his praise for the White Australia policy.

His party leader Bob Katter backed him “1000 per cent” after the controversial speech, which was littered with false and deeply offensive remarks about Muslim Australians.

Prime Minister Malcolm Turnbull and Labor leader Bill Shorten gave passionate speeches in parliament opposing Anning on Wednesday.

Turnbull said people who demonise Muslims because of the crimes of a tiny minority will only help terrorists.

“The days of the White Australia policy are long, long ago.”

Shorten moved a unanimously-passed motion in parliament praising the Liberal-Country Party government led by Harold Holt for beginning the dismantling of the White Australia policy in 1966.

Anning will move a motion in the upper house on Thursday calling on the government to hold a plebiscite to determine “who” is allowed to migrate to Australia.

A national vote would ask if Australians want to continue what he says is the current “indiscriminate” immigration policy, which “allows Muslims to come into this country”, or return to a program favouring white Europeans.

“We need a plebiscite to allow the Australian people to decide whether they want wholesale non-English speaking immigrants from the Third World,” he said in his speech on Tuesday.

Around 1942, Germany’s Nazi leadership established a plan called ‘The Final Solution to the Jewish Question’, which led to the genocide of more than six million Jews in occupied Europe.

Meanwhile, South Australian Centre Alliance MP Rebekha Sharkie, who was supported by Katter during her successful by-election campaign in Mayo, has rejected Anning’s speech and Katter’s response.

She condemned Anning’s comments, saying “racism should always be called out”.

Sharkie told ABC Radio Adelaide that she had been shocked by Katter’s support for Anning’s speech and if the by-election campaign was being run now, she wouldn’t accept Katter’s help.

– with AAP