More than 155,000 federal public service workers across Canada will be on strike as of 12:01 a.m. Eastern Time on Wednesday.
The Public Service Alliance of Canada announced Tuesday evening that they failed to reach a tentative deal with the employer before the 9 p.m. Eastern Time deadline.
"Our issues at the bargaining table still have not been addressed by this employer," president Chris Aylward told reporters shortly after the deadline.
"We are still a ways apart but we're staying at the table because we're still hopeful, and our goal is still to get to a tentative agreement."
Union members will stay at the table "as long as it takes" if the employer is willing to, said Aylward, and will remain on strike until the government "addresses our key issues at the bargaining table."
Earlier in the week, the union said some of the main sticking points had been wages, job security and language around remote work.
The strike will impact 120,000 members of the Treasury Board and 35,000 Canada Revenue Agency employees.
"Canadians can expect to see slowdowns or a complete shutdown of services nationwide, including a complete halt of the tax season, disruptions to employment insurance, immigration and passport applications; interruptions to supply chains and international trade at ports, harbours, and airports; and slowdowns at the border with administrative staff on strike," the union said in a news release on Monday.
Picket lines will be set up in communities across the country starting on Wednesday.