Canada will send "logistical" support to French forces fighting Islamist militants in Mali, Prime Minister Stephen Harper said Monday, but critics like former diplomat Robert Fowler are urging Ottawa to play a bigger role before the conflict escalates.

Harper said Canada will send a Royal Canadian Air Force C-17 cargo plane to Mali for a period of one week – on direct request from France.

Fowler, who was held captive by al Qaeda members in the region for five months, said he was “disappointed” by the announcement.

“I would have wished for more,” Fowler, who was kidnapped in December 2008, told CTV’s Power Play.

Al Qaeda-linked military extremists have been battling with government forces in Mali since a military coup last March, and now control much of the country's north, including the garrison town of Diabaly, which was taken on Monday despite an intense bombardment by French special forces.

"The establishment of a terrorist region in the middle of Africa is of grave concern to the broader international community, including Canada and our close allies," Harper said in a statement Monday.

He said Canada will help France with logistical support for future missions designed to shut down the rebels' advancement, though Canadian servicemen and women will not take on a combat role.

Harper said the French government requested heavy-lift aircraft support from Canada on Monday, in order to transport equipment to the Malian capital of Bamako, which lies about 400 kilometres from the fighting.

"The Government of Canada will support our allies in this request and will be providing one RCAF C-17 transport aircraft in a non-combat role to support operations for a period of one week," Harper said. "The RCAF aircraft will not operate in any combat zone."

But Fowler said stronger military intervention is necessary in Mali to prevent terrorists there from fanning out to other parts of Africa.

“My captors told me exactly what their game plan was,” Fowler said.

Their objective was to “spread the chaos, anarchy and turmoil” from Somalia’s coast on the Indian Ocean to Africa’s Atlantic coast, he said.

“One 8,000-kilometre band across the fattest part of Africa of absolute chaos,” Fowler said.

“If it does happen, we will have a humanitarian emergency the like of which will make Darfur look like a very small thing and then we will have to intervene. It’s easier to intervene sooner, rather than later and more expensively.”

Harper said Canada will also continue to provide humanitarian and development assistance funding to Mali.

"While the Government of Canada is not -- and will not be -- considering a direct Canadian military mission in Mali, Canada is prepared, consistent with the UN Security Council Resolution, to provide limited and clearly defined logistical support to assist the forces that are intervening in Mali," he said.

Earlier Monday, the French embassy in Bamako ordered the immediate evacuation of all French nationals from the town of Segou, which lies about 80 kilometres from the now militant-occupied town of Diabaly.

Last week, Harper met with Thomas Boni Yayi, president of the Republic of Benin and chairman of the African Union. The African leader called on NATO to join the African Union troops currently stationed in Mali.

In December the United Nations Security Council supported a proposal to send an African-led force of 3,000 troops into Mali, but also called for broader international support for the initiative.

With files from Andy Johnson