A month after workers at the Art Gallery of Ontario (AGO) walked off the job, their union says a tentative deal has been reached with the gallery.

In a message posted to X early Thursday, the Ontario Public Service Employees Union (OPSEU) said a tentative deal was reached after 16 hours of bargaining that went late into the night.

More than 400 AGO employees represented by OPSEU/SEFPO Local 535 walked off the job on March 26 after members rejected the art gallery’s offer.

The workers cover a range of roles, including assistant curators, archivists, food and hospitality staff, researchers, and visitor services staff.

The dispute mainly revolved around wages. The Union has said that more than 60 per cent of the gallery's workforce are part-time workers who make an average of less than $35,000 a year.

The gallery has been closed because of the labour disruption. It was not immediately clear when it would reopen.

-          With files from The Canadian Press