The cost of Canada's six-month bombing mission against the Islamic State group in Iraq was estimated at more than $100 million, according to officials Tuesday.

The independent parliamentary budget office put the tally at Can$128.8 million (US$103.8 million) to Can$166.40 million (US$134.1 million).

The budget office's report comes after Defense Minister Jason Kenney said the costs would top Can$122 million (US$96.7 million).

The costs of previous recent military missions, including Libya, spiralled far beyond initial estimates provided by the government.

Canada deployed 600 military personnel, six CF-18 Hornet fighter jets, two CP-140 Aurora surveillance aircraft, one C-150T Polaris air refueller, one C-17 Globemaster transporter and one C-130J Hercules aircraft to the region to join a US-led bombing campaign against IS in Iraq.

They are scheduled to return home to Canada at the end of March unless Ottawa extends the mission.