Public servants at Centrelink, Medicare and Child Support will start an "open-ended" campaign of strikes to force an end to their marathon industrial dispute with the Department of Human Services.

The CPSU told the department in a notice sent on Wednesday that rolling strikes will begin on March 17 and has warned that no end date was planned to the industrial action.

Public servants at Centrelink, Medicare and Child Support plan rolling strikes from March 17 over an ongoing industrial dispute. Credit:Marina Neil

"We're looking for some breakthrough. The end game is we're trying to get some sort of agreement," a spokesman said.

The union has threatened "significant" further action if the department did not move towards "a fair and reasonable settlement".