HALIFAX -- Nova Scotia students returned to their classrooms Tuesday, as the government abruptly backed off plans to impose a contract settlement on teachers.

The government had sent parents scrambling for child care by announcing on the weekend it would close schools to students. But on Monday, it quickly adjourned what was expected to be a week-long emergency session of the legislature, and announced schools would re-open.

The government said it reversed itself because the union addressed its safety concerns surrounding teachers' work-to-rule campaign, but the opposition said the Liberals had simply caused chaos.

"The government closed the schools ... on the pretext of safety," said Opposition Progressive Conservative Leader Jamie Baillie. "That pretext was blown out of the water for the lie that it is today and now the government's credibility is in tatters."

Baillie blasted Premier Stephen McNeil, who was a no-show at the legislature Monday.

Education Minister Karen Casey told reporters the government sought and obtained assurance about student safety from school administrators and an executive member of the teachers' union.

The union had directed its members to do the minimum amount of work required under the current agreement, including arriving at school 20 minutes before classes begin and leaving 20 minutes after they end.

"We are confident the Nova Scotia Teachers Union has modified its directives in such a way that schools can now open safely," said Casey, who read from a list of seven points that were issued by the union on Friday.

Casey said she now believes school administrators can "take all reasonable steps to create and maintain an orderly safe learning environment in our schools."

In addition, the minister said, "principals are now able to use cell phones more than 20 minutes before school begins and 20 minutes after school ends and that is an important communications tool."

When asked why she had moved ahead with the announcement about the proposed legislation forcing a contract on teachers on Saturday, Casey said she was never "officially notified" about the union's changes.

Casey's announcement came hours after House leader Michel Samson told reporters the labour bill would be delayed to allow for hastily organized talks about safety concerns around student supervision during the teachers' work-to-rule action.

Union president Liette Doucet said the government's actions on Monday were unnecessary.

"There was no question about student safety," said Doucet. "There were no directives changed today and there was no need to keep students out of class today."

Doucet confirmed the changes around student supervision were made by the end of the business day on Friday and were emailed to the government.

She said the government's actions had further served to erode trust with the union, but she wasn't sure how that would play out in trying to resolve the contract differences.

"I would say we have to get back to the table so that we can figure that out," she said.

Casey had previously said schools could be closed for up to a week, depending on the passage of a bill that would impose a contract on the union representing 9,300 educators in the province.

She said the closures were needed to ensure student safety, citing risks posed by the NSTU's work-to-rule job action that was due to take effect Monday. Teachers were being allowed into the schools, but students were being kept out.

On Monday, Baillie called for Casey's resignation.

"The only way forward now is through is through a sincere effort to work with teachers to make classrooms better. That cannot happen under this minister, she needs to go," he said.

But Samson said Casey has the confidence of the government and he said the proposed legislation, known as Bill 75, would be shelved for now.

"At this point in time this bill is not moving forward, that's the best I can give you," he told reporters.

Dozens of protesters, including some students and sympathizers from other public sector unions showed up at the legislature Monday to voice their discontent with the government's apparent move toward a legislated settlement to the long-simmering contract dispute.

Some carried signs saying "Let Teachers Teach" and "Negotiate Don't Legislate."

Contract negotiations between the province and the NSTU fell apart Nov. 25 after the sides agreed to meet with a conciliator following failed attempts to convene a conciliation board and to take the dispute to mediation.

The union membership has twice rejected a contract offer that the union executive recommended, and voted overwhelmingly in favour of a strike.