With the 2017/18 budget due to be discussed at a full council meeting tomorrow, the opposition group questioned why none of the £250,000 set aside for 'living wage business rate relief' by Labour in March last year had yet been spent.
The fund was set up to discount the rates of small businesses and charities in Sheffield to encourage them to pay a living wage to employees.
The Lib Dem spokesman for finance and resources Coun Penny Baker also asked why £185,000 set aside to bring empty shops back into use had not been invested.
Coun Baker said: “Living wage business rate relief is a great idea to help small local business and some of Sheffield’s lowest paid workers, but clearly it’s only worth doing if the money actually gets spent.
"This is just another example of how Labour in Sheffield are all talk and no action.”
Coun Baker suggested the council had failed to advertise the empty shops money, adding: “In these difficult times £435,000 could have gone a long way to helping people.
"Labour need to be making sure that every penny of taxpayer money gets spent in the best way.”
Labour's cabinet member for finances and resources Ben Curran said the council had taken 'a number of actions' to promote the living wage. He also pointed to the council's Renew scheme which brings empty shops back into use a 'great success'.
But he admitted it had taken longer than expected to get companies to sign up for living wage relief. The council also confirmed that the £185,000 - separate to the Renew scheme - had not been spent.
"It is, however, important to remember that the council are driving our local economy forward and pushing up growth," Coun Curran said.
"Just last month we had the announcements that both McLaren and Boeing will be setting up at the Advanced Manufacturing Research Centre and this will have a hugely positive effect to the smaller businesses on the supply chain.
"We will continue to work hard to drive growth for our economy, push employers to pay a decent wage and in turn push up the living standards for the whole of Sheffield. We recognise the need to continuously review our programmes to make sure they are as effective as possible in delivering for Sheffield people and we will continue to do so."
Coun Curran pointed out that the Lib Dems voted against the living wage relief plan at last year's budget meeting.
Green Party councillors, meanwhile, have called for money to be set aside to keep open Hurlfield View in Gleadless. The city's last remaining dementia respite centre will close in March after the NHS Health and Social Care Trust ended its contract two years early due to funding issues.
More than 5,000 people signed a petition against the closure.
Coun Douglas Johnson said: "It is imperative that the council finds the funds to keep Hurlfield View now, and then look to secure a future for its users in the long term.
"At a time where we face a crisis in social care, the expert and quality care that users of Hurlfield View receive cannot be lost.
“Respite care in a safe and well-loved centre is very important for taking pressure off families and for keeping people out of hospital and permanent care.
"Sheffield Greens are calling on the Council to listen to families, carers, and residents to and continue financial support for Hurlfield View. We will be supporting campaigners lobbying at the Town Hall this Friday hoping to achieve such a resolution."
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