By Colin Packham
SYDNEY (Reuters) - A prominent member of Australia's government is set to defect to form his own conservative party, media reported on Monday, further evidence of a shift towards the right that is weakening Prime Minister Malcolm Turnbull's already tenuous grip on power.
Adding to center-right leader Turnbull's woes, an opinion poll published on Monday showed that support for his coalition had slipped to its lowest since he took power in a party-room coup 17 months ago and that his Liberal-National coalition would easily fall if an election was held now.
Both developments came only days after Turnbull's leadership was questioned after he was berated by U.S. President Donald Trump over a refugee resettlement deal in a tense telephone call that hit international headlines.
On Monday, the Sydney Morning Herald and the Australian Broadcasting Corp. reported that Senator Cory Bernardi was about to abandon the Liberal Party, the senior coalition partner, to set up a more conservative wing - the biggest party split in a generation.
As well as highlighting internal party divisions, Bernardi's defection would also underline a hard turn to the right in Australian politics typified by the resurgence of Pauline Hanson's nationalist One Nation party.
Bernardi could not be reached for comment but another senior coalition conservative said the creation of a new party would indicate Turnbull had moved too close to the political center.
"It sends a signal to the leadership that we cannot abandon conservative causes, conservative principles and conservative policies," Nationals member George Christensen said in Canberra.
Political analysts also believed it meant Turnbull, who took the leadership from the more conservative Tony Abbott in September 2015, could soon face a leadership challenge himself.
"Cory Bernardi could appeal to conservatives that have so far continued to support the government. If that happens ... we could have another leadership challenge in the mid-year," said Haydon Manning, professor of politics at Flinders University in South Australia.
The loss of Bernardi would likely also make it even harder for Turnbull to govern after he won only a razor-thin majority at an election last year.
Monday's Newspoll, published in The Australian newspaper, showed the coalition with 46 percent support on a two-party preferred basis, where votes for minor parties are redistributed, eight points behind the Labor opposition.
Support for Hanson's One Nation - which first gained international notoriety in the late 1990s with its appeal to white nationalism - hit a national high of 8 percent, the poll showed.
The government has tried to limit the number of votes seeping to more populist right wing alternatives by taking an increasingly protectionist stance on foreign investment.
(Reporting by Colin Packham)