Australia will push ahead with its $17 billion purchase of F-35 Joint Strike Fighters, despite an announcement that Canada's new government will axe its intended purchase.

New Canadian prime minister Justin Trudeau has pledged to open a new tender to replace his country's aging fleet of fighter jets, dumping the F-35 program.

But Canada's withdrawal from the nine-nation deal to build the aircraft is not expected to impact upon the price for Australian purchases, Senate estimates has heard.

Joint Strike Fighters program manager Air Vice-Marshal Chris Deeble told a Senate committee tonight that Australia would move ahead with its purchase of 72 aircraft at a budgeted cost of $17 billion.

He said Australia had already purchased two JSF at the costs of $126.7 million each, but the cost of each aircraft was expected to average out to $90 million by 2023.

An additional eight are expected to be purchased in 2018, following by another eight in 2019.

Air Vice-Marshal Deeble said Australia would then purchase 15 aircraft a year up until 2023, when it would make a final purchase of 9 JSF.

Greens senator Peter Whish-Wilson questioned Defence staff on the reasoning for Canada's dumping of the controversial aircraft, but was told to "put that question to the Canadian government".

Canadian prime minister-elect Justin Trudeau said his Government will withdraw military from the fight against IS. ( Reuters: Chris Wattie )

During the recent election campaign Mr Trudeau said: "There are many other fighters at much lower price points that we can use that have been proven, that we will actually be able to deliver in a timely way."

Mr Trudeau has also told US president Barack Obama that Canadian fighter jets will withdraw from fighting the IS group in Iraq and Syria.

He has not said when the withdrawal will happen but his new government would be "moving forward with our campaign commitments in a responsible fashion".

Mr Trudeau told a press conference that, while Canada remains "a strong member of the coalition against ISIL", he had commitments to end the combat mission in favour of a humanitarian contribution.

The Joint Strike Fighter program also comprises Denmark, Italy, the Netherlands, Norway, Turkey, the UK and the United States.

The first Joint Strike Fighters will arrive in Australia in 2018 and enter service in 2020.

ABC/AFP