Prime minister David Cameron is expected to urge all public sector workers to join council staff in delaying strikes over pensions when he addresses the Local Government Association conference in Birmingham later today.

Mr Cameron is poised to urge civil service and education trade unions to call off planned strikes on 30 June. Up to 750,000 public staff are likely to join walk-outs on Thursday, after ministers outlined a series of proposals to reform public pensions – including plans to make staff contribute more to their retirement pots and to increase the public pension age.

Just as all major public sector unions were talking up the prospect of co-ordinated strikes over pensions this autumn, ministers and trade union leaders announced a minor breakthrough in relations yesterday.

Following heavy lobbying from councils and local government staff, Cabinet Office minister Francis Maude has agreed to hold separate talks over local government pension reforms – potentially staving off strike action by a large chunk of members from the public sector's largest trade union,Unison, which has 700,000 recruits in local government.

Following that announcement on 28 June, Dave Prentis, Unison’s general secretary, said:'I think we found today the government were willing to treat the negotiations seriously.'

Commenting on the wider threat of public strikes, Francis Maude said:'We believe both sides have a responsibility to see talks through and we would urge public workers not to strike while they are ongoing.'

Meanwhile, education secretary Michael Gove has come under fire for suggesting that parents could help to keep schools open on Thursday.