White Australians will be extinct within 40 years because Australian men are too busy smoking, drinking beer and taking drugs to procreate, a Muslim businessman has warned.

Halal certification chief Mohamed Elmouelhy told his Facebook followers the solution to this perceived demographic crisis for Australian women is for Muslim men to “fertilise them” and “keep them surrounded by Muslim babies” as part of what he foresees as the gradual Islamisation of Australia.

His observation was in response to a study by researchers from the Hebrew University, published in the journal Human Reproduction Update, which found declining fertility rates among men in North America, Europe, Australia and New Zealand.

“Your men are a dying breed, Australian women need us to fertilise them and keep them surrounded by Muslim babies while beer swilling, cigarette smoking, drug injecting can only dream of what Muslim men are capable of,” he said.

“Muslims have a duty to make your women happy.”

In an email to news.com.au, Mr. Elmouelhy said the now-deleted post was intended to “stir the bigots” who had allegedly attacked his Facebook page “using all manner of expletives and attacks possible including promises of physical attacks etc.”

“Last night Facelessbook deleted the post, yet venomous messages devoid of any humour addressed to me about Islam remain published,” he wrote. “You can see other messages from the bigots on other posts I have.”

In a longer version of the first Facebook post, Mr. Elmouelhy warmed to his theme that the future of Australia was tied to Islam.

“It will [sic] mandatory for all women to wear hijab or burka if they prefer, bikinis will be displayed in Museums but not on nubile bodies anymore,” he wrote.

“When that happens everything in Australia will be Halal certified. Bigots and pigs will be declared Haram and must not be approached or touched, they can live together in reserves. There will be a Halal butcher on every corner, all other butchers will be offered to convert to Halal or given [sic] a passage back to where their ancestors came from.”

The 2016 Census revealed that Muslims made up 2.6 per cent of the Australian population, up from 2.2 per cent in 2011.