In his column in The Sun newspaper, the former Top Gear presenter claims the fires are raging Down Under because “God didn’t want people to live there”.
The fires have claimed the lives of 23 people, an estimated half a billion animals have been killed and thousands of people have been forced to flee their homes.
“He created it as a continent far, far away where he could house all his experiments that had gone wrong,” he writes.
“It was his under-the-stairs cupboard for stuff he wanted to forget about.”
He continues: “Plainly, God is embarrassed. Because he’s decided to set fire to it.
“It’s been argued the fires raging across the country were caused by global warming or out-of-control barbies.
“But when you look at the footage, you know something biblical is going on. Those things are huge.”
He concludes by inviting Australians to move to the UK, where “it never stops raining”.
“This has happened before in recent years and there’s no doubt it will happen again,” he writes. “Which means people must accept that Australia isn’t meant for human habitation.
“So if you’re reading this down there, please come home. You’ll like it. It never stops raining. And we are better at sport.”
Many have taken to Twitter to condemn the presenter’s comments, labelling them “disgusting”, “insensitive” and “stupid”.
The American singer, who is one of Australia’s biggest selling artists, revealed her pledge of half a million US dollars (£382,043) in a post on Twitter.
“I am totally devastated watching what is happening in Australia right now with the horrific bushfires,” she wrote.
“I am pledging a donation of 500,000 dollars directly to the local fire services that are battling so hard on the frontlines. My heart goes out to our friends and family in Oz.”
Kylie Minogue, who is currently the face of an Australian tourist board ad, has also tweeted about the ongoing crisis in her home country.
“Humbled by the extraordinary efforts of the emergency services and volunteers in the ongoing bushfire crisis in Australia. @redcrossau @nswrfs @CFA_Updates @CFSAlerts @WIRES_NSW,” she wrote.
Australian Prime Minister Scott Morrison, who has been criticised for his response to the fires, called up 3,000 defence force reservists on Saturday as the threat of wildfires escalated.