Birmingham City Council has been accused of spending more than £2million on “non-jobs”.
Pressure group The Taxpayers' Alliance said the authority was wasting cash on posts such as a European officer and climate change officer.
The findings appear to have been endorsed by the Government.
In a statement responding to the report, Local Government Minister Grant Shapps said councils had forgotten they were responsible to taxpayers for how they spent their budgets.
But Birmingham City Council hit back, insisting it was right to lobby for grants from the EU and to ensure it was protecting the environment.
A survey by the Taxpayers’ Alliance found that Birmingham employed:
* Nine European officers at a cost of £246,523
* Twenty-eight diversity officers at a cost of £1,916,657
* Two climate change officers at a cost of £97,914
The total cost to the city was £2,261,094.
Chris Daniel, policy analyst at the Taxpayers’ Alliance, said: “Many household budgets are under huge pressure and council tax has doubled in the last decade, but this money isn’t necessarily going on the services households rely on most.
“Cutting down on staff doing unnecessary jobs is one way councils can save money without affecting those frontline services.”
The pressure group appeared to receive backing from Mr Shapps, who said: “In far too many cases there’s a duplication of roles in councils with the taxpayer left to pick up the bill.
“Councils need to be able to justify every penny to the electorate, yet some local authorities seem to have forgotten whose money it is.
“Our plans to publish all job adverts and expenditure over £500 online will expose wasteful councils, cut out a culture of excess and in the process protect frontline services.”
But a city council spokeswoman insisted: “We do not have diversity officers. We have officers working within the equality and diversity division who engage with other public agencies and community groups to ensure that everyone has the ability, knowledge and confidence to know how to access services, what help is available and what help they are entitled to.
"The council, like all local authorities, also has a duty to ensure it complies with government equality legislation.
“The city has accessed over £575 million in European funding over the last 25 years. European officers support the winning of these funds. With the withdrawal of other sources of funding European funds are becoming increasingly important again.
“Birmingham City Council is committed to addressing the issue of climate change because the benefits that can be reaped are not just environmental.
"By cutting its own carbon emissions, and encouraging citizens to do the same, the council is promoting the saving of money.”