Federal NDP leadership candidates argued over Canada's global standing, climate change and language during a French debate in Quebec City on Sunday.

The 90-minute debate, which got underway at 2 p.m. ET, comes ahead of the NDP's March 23-24 convention in Toronto.

It follows a surprise announcement by Quebec MP Romeo Saganash, who dropped out of the race on Friday because of meagre financial support and competing time demands.

Saganash's departure left seven competitors vying to take over the party's reins: party strategist Brian Topp, MPs Thomas Mulcair, Paul Dewar, Niki Ashton, Nathan Cullen and Peggy Nash and Nova Scotia businessman Martin Singh.

Sunday's debate focused on Canada's place in the world and the global economy.

All candidates attacked the Conservative government for its foreign and environmental policies.

Mulcair used his turn to critize Prime Minister Stephen Harper's support for oil sand production and development in Alberta.

NDP federal leadership candidates debate in Quebec City on February 12 (Clement Allard/Canadian Press)

Dewar was grilled about his connection to outspoken NDP member Charlie Angus, a unilingual anglophone.

Dewar has pledged to make the northern Ontario MP his deputy leader, after Angus endorsed his candidacy for leadership.

Sunday's debate was the first all-French event, and was moderated by broadcaster Jacqueline Pelletier and began with brief opening statements by each candidate.

Pressing concerns for the party include maintaining and building on the support the NDP gained in Quebec in last year's federal election — and the support that many people in that province gave to Layton himself.

'We have to not assume anything'

"There was a huge connection between Quebec and Jack and we have to not assume anything," Cullen said in an interview Sunday with Nancy Wilson on CBC News Network, prior to the debate.

The party's relationship to Quebec feels as if "we're still on a first date," Cullen said, adding that people in the province "obviously want to know us better."

Another issue being watched closely will be each of the candidate's ease in speaking French and how that could affect the party's continued support in the province.

Besides Saganash, Nova Scotia MP Robert Chisholm was another contender who left the race. Chisolm quit in December, acknowledging that he would not be able to speak French fluently by the time of the convention.

The party is currently under the leadership of Interim Leader Nycole Turmel.