Trade unions received a £108m subsidy from taxpayers in 2012-13, including £85m in paid staff time, according to a new report.

The research, conducted by the Taxpayers’ Alliance (TPA), found that at least 2,841 full-time equivalent public sector staff worked on trade union duties last year.

According to the report, Birmingham City Council was the local authority with the most staff working on trade union business, with 69 full-time equivalent staff.

Jonathan Isaby, chief executive of the TPA, said: ‘It is simply wrong that taxpayers continue to see their money used to pay thousands of trade union activists who organise strikes which disrupt the services that they rely on and pay for handsomely. Thousands of staff who should be working for the taxpayer are working for the trade unions instead. It’s welcome that the number has fallen, but far more must be done.

‘Tens of millions of pounds are being wasted and supporting aggressive political campaigns. The Government must crack down on this scandalous subsidy.’

A Birmingham City Council spokesperson said: ‘As Europe’s largest council, it should come as no surprise that Birmingham has more full-time staff involved in trade union activities than any other local authority.

‘Under the Employment Protection Act 1975, trade union representatives have a statutory right to reasonable paid time off from employment to carry out trade union duties and to undertake related training.

‘In addition, the Act gives the statutory right to reasonable unpaid time off when taking part in trade union activities.’

The report also warned that only 22% of the public bodies surveyed charged trade unions for deducting union subscriptions in the payroll process.