Nova Scotia's 9,300 public school teachers are set to return to work-to-rule job action Monday, and the tentative contract agreement with the province could be on the verge of collapse.

The Nova Scotia Teachers Union made the announcement about work-to-rule Friday afternoon.

"At this point, we don't know if we have a contract," union president Liette Doucet told reporters in Sydney.

A spokesman for the premier's office said Friday the contract offer remains in place and the government has no plans to rescind it.

At issue, according to the union, is Premier Stephen McNeil's interpretation of what the NSTU has been telling members is an extra two days off in the tentative agreement reached earlier this month.

McNeil told reporters Thursday they are not days off, but are meant for marking and preparation time.

'Premier has reneged'

Doucet accused the province of reinterpreting what had been agreed upon and said, "at this point, the premier has reneged on the agreement."

"The information that we have given our members is the correct information," she said. "If the premier comes out and gives different information, then he is going back on his word, he is going back on the word of his team."

The contract describes the two days of leave, with pay, as "self-directed preparation/development of the teacher."

It also says "teachers will not be required to provide reasons for such leave prior to or subsequent to the leave."

Vote still scheduled for Feb. 8

Meanwhile, McNeil said the two days in question are not meant to be vacation days and that was never part of the discussion with the union.

"I think any reasonable Nova Scotian would tell you that when teachers were telling us that classroom conditions were what their focus was, that if they were going to have more time it would be for prep in those classrooms, or marking," he told reporters at a meeting with other Atlantic premiers in Wolfville, N.S.

Nova Scotia Premier Stephen McNeil was in Wolfville, N.S., on Friday for a meeting with other Atlantic premiers and federal regional ministers in the Trudeau government. (CBC)

McNeil made his remarks before the union announced the return to work-to-rule.

The union's executive will meet to discuss this latest development, and also talk about whether to continue recommending the tentative agreement to its members.

Teachers are scheduled to vote on the deal Feb. 8. A union spokesman said the vote is still set to go ahead.