The Community and Youth Workers Union, has not said how much it is seeking.
But it rejected as "insulting" the 3 per cent rise suggested by employers when both sides last met in October. It also says local authorities are short-changing the service by spending too little.
The union, formed in 1938, has never taken national action over a pay claim. But things came to a head following a weekend conference last November. The union is holding another rally tomorrow at Adrian Boult Hall, Birmingham.
The result of a ballot of 3,500 members will be known on February 9.
Negotiations have been delayed for weeks because the employers' side - the Joint Negotiating Committee (JNC) - has been re-organising. "We've had a request from the staff side for a meeting in March," said Mike Walker, secretary to the employers, "But I want to see if we can get the leadership on both sides together first. There is pressure on local authorities to keep council taxes down. This is bound to have an effect on the employers."
However, the union says members are entitled to a better deal as the government has given councils 5.9 per cent extra this year for youth services. "The minister has just written expecting them to meet tougher targets," said union general secretary Doug Nicholls. "That means more work for our members." The CYWU has long resented the pay gap with teachers: a newly qualified teacher can expect pound;18,105; the equivalent youth worker pound;14,643.
Birmingham city councillor Les Lawrence, new chairman of the streamlined 11-strong employers' side, said it would be impossible to discuss the claim until the ballot result was known. But he added: "Local authorities are on a tight budget and there's very little room for manoeuvre."