Prime Minister Justin Trudeau, centre, gestures as he attends a campaign event for Liberal party byelection candidate Stan Sakamoto in Medicine Hat, Alta., Thursday, Oct. 13, 2016. The largest union representing federal workers is ramping up its campaign against the Liberal government, turning the prime minister's words against him.THE CANADIAN PRESS/Jeff McIntosh

OTTAWA - The largest union representing federal workers is ramping up its campaign against the Liberal government, turning the prime minister's words against him.

The print and radio advertisements paid for by the Public Service Alliance of Canada (PSAC) are hoping to use Prime Minister Justin Trudeau's promise of a revamped relationship with civil servants to prod the Liberals to change collective bargaining tactics.

The campaign is scheduled to launch Monday and the print ads are addressed to Trudeau with "you said you'd be different" emblazoned across the top and the words, "make good on your word" at the bottom.

The ads also include wording from Trudeau's open letter to federal bureaucrats telling them that his government wanted a different kind of relationship with the hundreds of thousands federal civil servants, many of whom felt under siege with the previous Conservative government.

"It has been a year since the election. The tone has changed, but it's now time for action," said PSAC national president Robyn Benson.

Contract talks with PSAC have dragged on for more than two years, with negotiators returning to the bargaining table late last month for the first time in nearly three months. Treasury Board of Canada, which bargains on behalf of the government, signalled in June that it was not prepared to back away from proposed changes to sick leave for about 90,000 workers.

The government has proposed allowing its employees eight days of sick leave annually, with the ability to carry over two days into the next year.

Public servants currently get 15 days a year of paid sick leave, which they can roll over and bank from year to year.

Treasury Board's plan would see the existing bank, which has about 15 million days of unused sick leave, abolished.

The union said it has proposed contract language that would result in fairer treatment for workers when changes are made to the delivery of government services.

It has also asked for wage increases totalling nine per cent over three years.

Earlier this year the government had offered 0.5 per cent wage increases in each of three years, pay hikes it has already promised its executives.

News from © The Canadian Press, 2016