Bus drivers and engineers working for Metroline in London are set to vote on a pay offer.
Their Unite union is to recommend rejecting the offer, as anything less than a cost of living increase will be unacceptable.
Metroline says it will make £l million per month profit.
London Underground train drivers on the Victoria Line are balloting for strikes.
The drivers’ RMT union says they are forced to work overtime, hassled when off sick and are denied reasonable requests for annual leave. The ballot runs until Wednesday 28 August.