Birmingham City Council workers took part in a one-day strike over new pay deals during the final day of the Liberal Democrat conference.
The rally was held amid anger over salary reductions and other changes to the new deal, dubbed the “Martini Contract”, because they claim it means they could be made to work “anytime, any place, anywhere”.
Carers, library staff and neighbourhood office workers all took part in the action, chanting against Lib Dem leader Nick Clegg and cuts they claimed would hit the lowest-paid staff.
Care assistant Paula Smith, aged 45, from Erdington, said the contract would cut her pay by £5,000 a year.
She said: “The new contract means we can be asked to work anywhere and any time for a basic rate of pay. They’re cutting weekend pay and shift allowance so I’ll be losing £5,000 a year.
"They’re not considering what they’re doing to people. They are only taking money off the lowest graded, the highest paid are not affected.”
The city council said “the majority” of services remained operational despite hundreds of workers walking out on Wednesday.
The Register Office, benefits service, parks and visitor centres, community museums, trading standards and refuse and recycling collections were among the services which stayed open.
The council claimed that by 12.45pm, only 864 employees of 21,288 non-school staff had taken part in the industrial action led by Unison, which has about 10,000 members working at the authority.
Graeme Horne, joint branch secretary of Birmingham Unison, said the council “always under-estimated” action taken by trade unions.