The council has been accused of putting jobs and services at risk among dozens of charities and community groups across Brighton and Hove.
The services currently support some of the most vulnerable people in the area but may lose vital funding.
The claims follow a proposal to delay the process of awarding contracts to community and voluntary sector organisations.
The Conservatives believe that the new Labour council wants a six-month delay so that it can start a process of bringing contracts in-house – under council control.
And they accused Labour of trying to slip the decision through undemocratically.
Concerns among those running local charities come after a row earlier this year over the sudden way that funding was withdrawn from Possability People.
The decision to scrap the cash for the disability advice service was made by the Brighton and Hove Clinical Commissioning Group (CCG) with the support of Brighton and Hove City Council.
The move was not signed off by any democratically elected councillors.
When they found out, they stood alongside Possability People in a protest outside Brighton Town Hall, with Labour and the Greens prominent among the critical voices.
But today the Tories said that Labour was falling back on its latest manifesto to justify its threat to charities and the way that those charities were able to support local communities.
The manifesto, which one Tory said was Momentum-inspired, promised to “independently audit all outsourced services and bring services in-house if it will achieve a higher level of social value and improve the development and retention of a highly skilled council workforce”.
The Conservatives said that they were hoping for the Greens to stick to their election pledge to support local charities and voluntary groups.
The Green manifesto said: “Brighton and Hove is fortunate in having a very active community and voluntary sector that works in neighbourhoods the council is less able to reach.
“A Green council will support investment and oppose cuts to the sector.
“We will help community groups access resources and in-kind support through providing buildings, meeting rooms and funding advice.”
The Conservatives said: “With months in the preparation and with third sector volunteer organisations ready to submit their bids for the next three years’ funding, the Labour administration has dramatically attempted to halt the process.
“Without following any due process Labour has written to all organisations advising that they are delaying the tendering of grants so that they can ensure that the ‘principles fit with their manifesto priorities’.”
The council said that it would extend existing levels of funding for six months – to September next year – as a result of the proposed delay.
Councillor Simson said: “We all know what this could really mean. Labour, unhappy with engaging and funding the voluntary third sector, may well be considering bringing the services back in-house.
“It is shocking that Labour completely by-passed the democratic process to deliver on previous committee decisions.
“It is also worrying that they pledge monies to extend the existing contracts with funds they do not have and cannot guarantee, irrespective of the fact that they have no authority to do so.
“Our many volunteer organisations provide fantastic support to our city and it is sad to see how Labour underrate their value and may wish to disband them.
“We are delighted that officers have listened to the Conservative group and recognised this unlawful manoeuvre – and are now bringing to the next Neighbourhoods, Inclusion, Communities and Equalities (NICE) Committee a report that gives members the ability to vote on Labour’s proposal.
“The Conservative group will vote against this proposal and we hope that the Green group will support us.
“Subsequently, the Conservative group will call for a Special NICE Committee or an Urgency Sub-Committee to consider the already prepared report that Labour has shelved to enable the grant bidding process to continue and support our wonderful volunteers.”
One community group told Brighton and Hove News that charities and voluntary organisations were often able to attract external funding that was not available to councils.
They provide an outlet for volunteers – including many retired people – to share their spare time and expertise on things that are often low priority for council bosses and health chiefs.
Another said: “Councils aren’t always good at recognising need, particularly when it’s for something specialised and perhaps affects very few people. Or it might not be cost-effective.
“But support groups, for example, can provide a lifeline, especially at short notice or when things are especially difficult. They might work alongside parents and carers and just help them to keep going.
“The price of failure in those circumstances is really high for the individuals involved and, as a result, could hit council budgets much harder than the council’s current modest outlay.”
Councillor Kate Knight, the new chair of the Neighbourhoods, Inclusion, Communities and Equalities Committee, said: “The group leads on the Neighbourhoods Committee and I have been in touch ahead of the meeting on Monday about the next stage of the Third Sector Commission.
“This is a hugely important matter. I’m sure the outcome of these discussions will be very positive.”
The NICE Committee is due to discuss the proposed delay at Hove Town Hall on Monday (1 July). The meeting is scheduled to start at 4pm and should be open to the public.
This is a ridiculous move and is likely to have damaging consequences for the specialist services involved. The 3rd sector is precarious enough without having to wait an additional 6 months to find out if your organisation is going to be funded. Staff turnover is high enough in the sector as it is so one consequence could be the loss of experienced and dedicated staff. Not to mention the impact on morale and motivation. This move is driven by blind ideology without any thought for the consequences. Another reason why I’m now relieved that I didn’t get elected.