For Mathias Cormann, stepping into the role as acting prime minister is a testament to the great Australian gift of opportunity.

“Australia is a country where if you put your shoulder to the wheel and work hard and do the best you can to make a difference, there is no limit to what you can achieve,” the Belgian migrant told Sky News.

The federal Finance Minister will step into the role of acting prime minister for five days this week as Prime Minister Malcolm Turnbull heads to the United States.

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But the job comes at a tumultuous time for the government, which is reeling from the fallout over Deputy Prime Minister Barnaby Joyce’s affair with a former staffer.

Senator Cormann is the fourth in line to the job – it would have normally gone to Mr Joyce but the Nationals leader is taking leave amid the saga over the affair. Third in line, deputy Liberal leader Julie Bishop, will also be away overseas on official business.

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While some have jokingly called it a ‘Stephen Bradbury’ moment, Senator Cormann is regarded by some commentators as a stable hand during a crisis.

He’s been the Finance Minister since 2013, is the leader of the Government in the Senate, and has acted as election campaign spokesman for the last two elections.

But the temporary post is a major step for someone who while fluent in German, French and Flemish, couldn’t speak English until age 23.

It was at that age when he first came to Australia to follow a girlfriend on a holiday.

The relationship didn’t work out, so the story goes, but a new one had formed with a new country.

Two years later, he’d migrate to Australia and set up a new life.

He gave up a career in law to pursue one in politics and slowly climbed through the ranks of the Liberal party. He became State Senior Vice-President of the WA Liberals between 2004 and 2008, before launching into federal politics through the Senate.

This week, he will also be the first senator to act as prime minister since Labor’s Chris Evans in 2008.

But Senator Cormann is playing down this opportunity to be acting prime minister while Mr Turnbull is away.

“It will really just be business as usual,” he said.

“The Prime Minister is still the Prime Minister, even when he is in Washington. I will just be his man on the ground here in Australia.”