Sun Media Corp. locked out 140 workers at Le Journal de Québec on Sunday.

The lockout of editorial and office staff at the Quebec City newspaper took effect amid a negotiating impasse over working conditions.

Luc Lavoie, a spokesman for Sun Media's parent company, Quebecor Inc., said the paper will continue to be published during the lockout.

Lavoie said the company is asking journalists to adapt to the changing multimedia world by providing content for the internet in different formats.

"The industry is in complete mutation right now,'' Lavoie said in an interview.

"Circulation is down everywhere in North America. The industry is undergoing profound change, so we must adjust working conditions so we can be confident newspapers, businesses like ours, will be sustainable into the future.''

The company wants to shift to a five-day work week from the current four days and to reduce the newspaper's workforce by centralizing some functions like classified ads.

Lavoie said the newspaper's reporters are the best paid in the industry, with journalists averaging $86,000 per year and section editors more than $100,000.