Stephen Harper planning discussion of next steps in fight against ISIS

Canadian pilots fighting in the skies over Iraq and Syria may soon find out how much longer the federal Conservatives think they'll need to be there, the party's leader said Monday.

At an election rally, Stephen Harper said he intends in the coming days to discuss Canada's contribution to the international coalition fighting Islamic militants in those countries, but suggested the fight is far from over.

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"The intervention has had the effect of largely stopping the advance of ISIS, particularly in the north of Iraq and to some degree in other parts of Iraq and Syria not maybe as much we'd like," he said.

It's been a year since the plight of thousands of Yazidis trapped on a mountaintop by Islamic State of Iraq and Levant fighters moved the U.S. to start pulling together countries for an air war designed to stop ISIL from taking over more land in Iraq.

Canada joined the fight in October 2014 for an initial six-month mission, which was expanded this March for up to a year. Canadian fighters are now also bombing ISIL positions in Syria.

Things have improved, Harper told the rally.

"A year ago, they were literally on the verge of sweeping over the entire region, so at least that has been halted."

Canada has six CF-18s, an aerial refueller, two surveillance planes and about 600 personnel involved in the air war, as well as 69 special forces training Kurdish fighters. In recent days, according to the Defence Department website, Canadians bombed an ISIL ammunition cache and boats used to transport ammunition, as well as ISIL fighting positions.

Canadians have also been accused of killing civilians during a bombing run in January though a U.S.-led investigation found no substance to those allegations.

'A long and sustained strategy'

U.S. military information suggests that as of April, ISIS maintained control of about 70 per cent of the space in Iraq it had a year ago, while its influence in Syria remains largely unchanged.

Harper called radical fighters taking over what he called "ungoverned" parts of the world a growing phenomenon.

"To protect our country, we are going to have to have a long and sustained strategy with our international partners," he said.

Security has been a key election theme for the Conservatives. Earlier this month, Harper slammed his opponents' desire to focus on humanitarian help as little more than "dropping aid on dead people."

But the main theme of Harper's week is expected to be the economy, with new data coming Tuesday likely to show Canada was in a technical recession in the first half of the year.

Harper began the fifth week of the campaign watching three-year-old Lysander Konstantinakos, son of the Conservative candidate for Ottawa-Centre, sing his ABCs during a photo op at the family's downtown Ottawa home.

Harper's main message Monday, while delivered in front of party faithful, was aimed at voters listening to another ABC refrain Anyone But Conservatives.

"When Liberal and NDP politicians make expensive promises, the dollars don't grow on trees," he said.

"They end up coming out of the pockets of middle class families and we Conservatives are not going to go down that path."

Harper headed to Toronto after the morning Ottawa event, with stops along the way, but he had no other public speeches planned for Monday.