Maverick backbench MP Craig Kelly has resigned from the Liberal Party and will sit as an independent, moving to the crossbench and cutting the government’s lower house majority to just one seat.

Mr Kelly, Member for the seat of Hughes since 2010, handed a letter to Prime Minister Scott Morrison at a party room meeting on Tuesday morning. He said he didn’t want to be a “distraction” for the government, in the wake of his controversial support for headlice drug Ivermectin as a potential COVID treatment – a claim that is not supported by Australian medical advice.

Mr Kelly’s shock defection leaves the Coalition with just a one-seat majority in the House of Representatives. He has committed to guaranteeing supply to the government, so his move will not threaten the Coalition’s hold on power.

He plans to run at the next election, most likely as an independent. However, speaking to The New Daily inside his Parliament House office, Mr Kelly did not rule out rejoining the Liberals if he was invited back.

Several journalists huddled outside the door of Mr Kelly’s Parliament House office just after news broke. The door was firmly locked, with just a black and white photograph of Winston Churchill and long-serving Liberal Prime Minister Robert Menzies in his window.

Mr Kelly is expected to make a statement to the House after Question Time about 3.30pm, to further explain the reasoning behind his decision.

Tanya Plibersek and Craig Kelly clash in a corridor at Parliament. Photo: Getty

Nationals MP Barnaby Joyce was reportedly inside Mr Kelly’s office shortly after his defection was announced. One Nation Senator Malcolm Roberts also walked past Mr Kelly’s office, on the other side of Parliament House to his Senate office, but left after spotting a crowd of journalists. Bob Katter, the long-serving Member for Kennedy, knocked on the door and shook Mr Kelly’s hand, to “congratulate” him for his decision.

There has been talk of whether Mr Kelly could switch to the Nationals or another party, after leaving the Liberals. As recently as two weeks ago, Mr Kelly was adamant he would defend his seat of Hughes at the next election, standing as the Liberal candidate, but speculation swirled as to whether he may face another pre-selection challenge, as in the past two elections.

Mr Kelly was reportedly only spared being dumped as Liberal candidate in prior campaigns after last-minute interventions by Prime Ministers Malcolm Turnbull and Scott Morrison.

However, speaking to The New Daily, Mr Kelly said he had not had conversations about joining any other party – including the Nationals, One Nation, or Mr Katter’s Australia Party.

Mr Katter told The New Daily it would be “crazy” for Mr Kelly to join his party, or the Nationals.

Mr Joyce reportedly told 7 News that he would “love [Mr Kelly] to join the Nationals… I’d do what I could to encourage it”.

Mr Kelly also told TND he had quit as chair of the Joint Committee on Law Enforcement, which he added was “about a 14 per cent pay cut”. He explained that the chairperson must be from the government, so when he left the Liberals, he couldn’t stay as chair.

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Mr Kelly has been a controversial figure throughout the pandemic, sharing coronavirus misinformation, and had faced being disendorsed by the Liberal Party ahead of the next federal election.

In recent weeks, Mr Kelly has continued to post on Facebook about the controversial drug ivermectin as a COVID treatment. His posts were routinely among the most popular of any Australian politician.

In early February, following a highly publicised confrontation with Labor shadow minister Tanya Plibersek in the halls of Parliament, Mr Kelly was sternly told by the PM that his views on COVID were potentially affecting the vaccine rollout.

It took months for Mr Morrison to make a public statement condemning the Hughes MP, who had been promoting two unapproved drugs on his since-removed Facebook page.

He has also long questioned the science behind climate change.

Mr Kelly threatened to quit the Liberals ahead of the 2019 election when he faced a challenge to his seat from within the NSW branch but was saved by Mr Morrison.

Senior Labor MP Linda Burney says Mr Kelly has been a “thorn in the side” of the Liberals for some time.

“The government has the slimmest of majorities in the parliament now,” she said.

Mr Kelly has assured the government he will continue supporting it on votes in the House of Representatives.

-With wires.