A leading voluntary sector figure is set to launch a scathing attack on local authorities at next month's Charity Fair.
Kevin Curley, chief executive of the National Association of Councils for Voluntary Service, will accuse councils of ignoring charities' needs and failing to take them seriously.
He will also warn delegates they face a grim future unless they get to grips with the new local government agenda and adopt a more hardline approach.
"In some parts of the country we have waited too long for local government to take the voluntary and community sector seriously," he said. "We should now pursue the offending local authorities with every stick available to us."
Curley added: "A new type of local government is being created. Councils are going to have huge, multimillion pound budgets and the sector has to have a say in how this money is used."
A host of new initiatives, such as Local Area Partnerships, Local Strategic Partnerships and Local Area Agreements, compel local authorities to collaborate with other organisations - but many are ignoring them.
Charities can strike back, however, through the Audit Commission's Comprehensive Performance Assessment process. This measures the effectiveness of local auth-orities' work within such partnerships.
"It's both significant and welcome, but we must make sure voluntary groups know about it and how to take advantage of it," said Curley.
Sarah Wood, director of economic and environmental policy at the Local Government Association, admitted some councils needed to raise their game.
"This is certainly an issue," she said. "And we want to work with the voluntary sector to address it.
But she added that charities had to shoulder their portion of the blame.
"There can be variable performance on both sides," she said.
Curley will lead a session on the relationship with local government at Charity Fair, which takes place on 12, 13 and 14 April.
NACVS chief executive Kevin Curley is to accuse local councils of ignoring the needs of charities
Curley will tell delegates at next month's Charity Fair to take a more hardline approach in their government dealings
Sarah Wood of the Local Government Association has admitted to 'variable performance on both sides'.