Binmen in Birmingham could resume strike action after their union accused councillors of failing to honour an agreement which ended a long-running pay dispute.
Unite said its members were furious that Birmingham City Council had yet to implement a deal signed in March by four trade unions representing bin collection staff, who voted to accept new working conditions after staging a series of strikes.
Unite regional officer Lynne Shakespeare said the union was now looking at all the options available to members, including the possibility of restarting industrial action.
"If this agreement is not implemented, we shall be forced to meet with our membership again and possibly restart the strike action," the union official said.
"The council has made no attempt to honour the agreement which we all signed in March.
"It seems that the council enjoys being in dispute and seeing tonnes of rubbish on the streets, especially during the summer months.
"If the council did not want to reach an agreement, why did they bother to make one with us - it all seems to have been a complete waste of time."