Dave Prentis, general secretary of Unison, told his union’s national conference in Brighton that public sector workers will be “making a stand” later this year.
He revealed he has been holding talks with unions representing teachers, probation officers and other public sector employees about co-ordinated strikes.
“The aim is to make it an autumn for this coalition to remember, a wave of action never witnessed before, an autumn with plans afoot to ballot our health members, our police staff, our food agency staff.”
Unison is already balloting over half a million local authority workers for strikes over pay, with a massive walkout planned for July 10 if there is a yes vote.
Members of other unions are also being balloted for a strike on July 10, while further walkouts are set to be launched later in the year well as a national demonstration in October.
Mr Prentis also had a strong message for Labour, saying workers were fed up with “flaky” ideas and lack of support.