Immigration hardman Scott Morrison is new Aussie Treasurer

Scott Morrison, Treasurer of Australia
WILLIAM WEST | AFP | Getty Images

Australian Prime Minister Malcolm Turnbull has appointed Scott Morrison as treasurer, handing the conservative lawmaker the top economic job in his new cabinet in an effort to mend party divisions following the ouster of Tony Abbott.

Morrison won both praise and condemnation as immigration minister for his ruthlessly efficient implementation of Australia's policy of turning back boatloads of asylum seekers arriving from Asia.

Most recently, Morrison had been tasked with steering through difficult welfare reforms as social services minister.

Other changes in the much anticipated cabinet reshuffle were the appointment of Maris Payne as defense minister, one of five women in the new cabinet, and former Education Minister Christopher Pyne as industry, innovation and science minister.

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"Today, I'm announcing a 21st century government and a ministry for the future," Turnbull told reporters in Canberra. "Very big changes to meet very big challenges to help all of us seize very big opportunities."

Turnbull's Liberal Party and its junior coalition partner, the National Party, won a landslide election in 2013 under Abbott, promising stability, economic reform and to stop asylum seekers arriving by boat.

Abbott was ditched on Monday after months of destabilizing infighting and a series of gaffes and perceived policy missteps.

Turnbull, a multimillionaire former investment banker, lawyer and technology entrepreneur, is Australia's fourth prime minister in just two years.

A liberal in favor of marriage equality and action on climate change, Turnbull is popular among the business community and wider electorate but held in deep suspicion by some right-wing members of his ruling coalition.

His rise to power gave the Liberals a lift in opinion polls and was credited with helping them in their weekend by-election win in Western Australia.

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Veteran political commentator Malcolm Mackerras said the new cabinet should give the government a boost as it heads into elections expected next year.

"I think Turnbull will lead them to a second victory," he said.

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Along with Foreign Minister Julie Bishop and Trade Minister Andrew Robb, who retained their portfolios, Morrison, 47, was seen as one of the few stars of the Abbott government.

Morrison takes on his new role as Australia's $1.5 trillion economy grapples with the end of a powerful mining boom and as top trading partner China adjusts to slower, more consumer-focused growth. Former treasurer Joe Hockey would be resigning from parliament, Turnbull said.

Defense Minister Kevin Andrews was dropped after less than a year in the job.

The removal of Abbott and his loyalists is seen as a setback for a Japanese bid to build stealth submarines for Australia.

Abbott and Japanese Prime Minister Shinzo Abe enjoyed a close relationship that saw Japan emerge as the early front runner for the A$50 billion ($36 billion) programme.

But Japan's reluctance to commit to building the majority of the submarines in Australia has seen it lose ground to German and French proposals.

The new cabinet is expected to be sworn in on Monday.