France has pledged more troops to Nato's force in Afghanistan
Canada will continue its frontline role in southern Afghanistan after the February 2009 deadline it has set.
It had asked for a further commitment of troops from its Nato allies during a summit in Romania.
France earlier confirmed it would send a battalion of troops to the east of the country.
Canadian Prime Minister Stephen Harper said that although that commitment was not enough overall, it was a vital step in the right direction.
Of the demand for reinforcements, Mr Harper said: "We have satisfied those conditions."
France's contribution of around 800 troops was confirmed in a speech on Thursday morning to a session of allied leaders by President Nicolas Sarkozy.
"I have decided to reinforce the French military presence with a battalion deployed in the eastern region," he said.
Threat to withdraw
The US said the pledge would free up some of its troops to bolster Canadian forces in the south.
Canada had threatened to withdraw its contingent in Kandahar province unless other Nato countries sent reinforcements.
Having suffered rising casualties in the south, it wants its forces to be reinforced with a 1,000-strong battle group, along with helicopters and unmanned aircraft.
Gen Daniel McNeill, commander of the Nato-led International Security Assistance Force, (Isaf) has asked for as many as 10,000 more troops, in the form of two combat brigades and a brigade of trainers.
Isaf's numbers have risen from 33,000 troops to 47,000 in the past 15 months, in response to a resurgence from the Taleban and other militants.
In other developments at the summit in Romania, Nato has confirmed it will not yet offer membership to Georgia or Ukraine, after the 26-member alliance was split amid strong objections from Russia.
Moscow said Nato's promise that the nations would join one day was a "huge strategic mistake".