UPDATE: Ottawa Citizen, Sun workers could be locked out by Postmedia

Postmedia Network has told staff at the Ottawa Citizen and Ottawa Sun it will lock out union employees starting Thursday if they reject or refuse to vote on its final contract offer this weekend.

The offer's deadline was initially set for monday, but has now been pushed back to Wednesday. If the offer is rejected, Postmedia says they will lock out staff starting at 12:01am on Thursday.

The vice president of human resources and labour relations at Postmedia says in a letter to staff that a lockout is not the company's preferred course of action.

But Chris Krygiel says both sides have to "move on" from a collective agreement that expired nearly three years ago.

Union vice-president Lois Kirkup says the company is asking for significant cuts on top of agreed-upon concessions that included a shift to a defined contribution pension.