Ambulance response times could be affected by industrial action started by paramedics today in a dispute over meal breaks.

Around 450 Unison members who work for the North East Ambulance Service (NEAS) agreed to ban overtime after it was announced that staff will no longer be paid for breaks, although they will be expected to remain on standby.

Ray McDermott, Unison branch secretary, said the overtime ban could result in the public waiting longer for ambulances as there would be fewer crews available.

The service, which has around 620 employees, relies on overtime as a way of covering for holidays, training or sickness.

Mr McDermott said: ''This overtime ban will carry on as long as members tell me. Something has to change very quickly, and obviously the longer this goes on the bigger effect it will have.''

He said that the dispute was initially with NEAS but they were later told that the government had not provided funds to pay for paramedics' meal breaks. ''The two other emergency services get paid for their breaks, so why shouldn't we?''

The dispute arose from the NEAS's implementation of the Department of Health's Agenda for Change.

Simon Featherstone, NEAS Chief Executive, said in a statement: ''Whilst discussions to date have not resulted in an agreement, progress has been made on how the Trust could achieve the 37- hour working week in line with the advice received jointly from the NHS Pay Modernisation Unit and Unison.

''Regrettably, despite this, Unison felt it had to continue with its planned action.

''We have contingency plans in place to minimise disruption to patient services.

''As always, we prioritise our responses to life-threatening cases and we will continue to do so effectively.''