Fears were raised last night that some Norfolk charities and voluntary groups could be forced to scale back or close at a time when they are needed most because of public service cuts.

Officials from the county's leading charitable, voluntary, and not-for-profit organisations warned that a 'perfect storm' was approaching as a result of local and central government budget cuts, which will hit services for the most vulnerable members of society.

Their fears come as the third sector is expected to pick up the pieces of huge public spending cuts as part of the coalition government's Big Society vision.

However, the leaders of Norfolk's charities and voluntary groups last night said it was a mistake to think that volunteers could take on the extra responsibility without financial support.

They also expressed their concern at the proposals to cut 750 full-time jobs at Norfolk County Council as part of plans to slash its budget by �155m over the next three years.

The reduction of council budgets and the shake-up of the NHS has caused many charitable and voluntary organisations in Norfolk to look at their books and review the way they work.

Many told the EDP yesterday that it was difficult to take on new work without fresh funding, while others said the Big Society represented an opportunity for growth.

Brian Horner, chief executive of Voluntary Norfolk, which helped recruit 9,000 volunteers for organisations last year, said that while Norfolk County Council had made some changes following the Big Conversation, there was still great concern among local groups.

'We are not just worried about our own future, but the impact on the vulnerable people that rely on those services. There is a serious worry across the voluntary sector, not just Norfolk but across the country, from a double impact from cuts from national government and cuts to local funding, which will lead to this perfect storm.'

'I think we will see a real risk of some voluntary organisations, just as they experience an increase in demand for their services, cutting staff and in some cases not be able to continue. Whilst we are keen to work with local bodies, we can not do it for nothing. Goodwill does not pay the mortgage,' he said.

It comes as a voluntary sector conference is set to take place in Norwich tomorrow to discuss the way forward for children and young people in Norfolk, in light of local authority cuts.

The Association of Chief Executives of Voluntary Organisations (Acevo) warned this week that the sector could face a �4.5bn hit over the next year, with 90pc of organisations dependent on state funding.

Richard Draper, chief executive of the Benjamin Foundation, which provides services for vulnerable young people across the county, said the charity was waiting for more 'clarity' over where the county council cuts will fall. He added that the worst case scenario would be 'devastating' and would lead to job losses.

'My big nervousness is the rapid way that this is taking place and we can see a significant number of voluntary agencies under treat of closure and we will be looking around in years to come asking 'where have they gone?''

'We will be working really hard to try and secure our existing provision and as a result of public cuts there is more pressure on capacity. There has already been a massive cutback in Connexions and a number of young people are looking at our services to fill that gap,' he said.

Emon McGrath, community development manager for Age UK Norfolk, said the charity was keen to be involved in the restructuring of public services.

'It is too early to know what we would be asked to do. We have not talked about doing extra, but doing differently and similarly to the county council we have to look at what we do. We are trying to respond in a positive way that tries to make the best of the situation and try and make sure older people do not lose out,' he said.

Chris Hoddy, chief executive of Break, which has contracts with Norfolk County Council to provide eight children's homes, with 37 beds, residential family assessment unit and mental health services said he was 'cautiously optimistic' about the future.

'We can see that organisations like Break could be in a position to pick up more work of that nature. Norfolk has 200 children placed outside of Norfolk and anything that can increase capacity is good for everyone.'

'We could be in the situation where we are being asked to bid for new contracts and some of the older ones are being taken away,' he said.

Derrick Murphy, leader of Norfolk County Council, said the conversation would continue with communities even when the budget proposals are considered at a full council meeting on February 14

'We know a number of charities and voluntary sector groups are keen to explore how they can do more and several town and parish councils have expressed an interest in areas such as gritting/salting etc. We look forward to those discussions and working with them.'

'It's also right to say that some concerns were raised about how such a transfer might happen, how we could ensure quality and standards were maintained and questioning our capacity to support those who do take on additional responsibilities,' he said.