Lothian buses. Pic: Lisa Ferguson

The Unite union announced it would begin a formal four-week ballot of its members at Lothian Buses next Thursday after a consultative vote last month found 94 per cent support for strike action.

And the union said if the drivers back a strike the stoppage was likely to coincide with the start of the Festival.

The row dates back to December when a bus driver was sacked and around ten others were suspended over posts on a closed Facebook group in what was said to be the latest example of a growing problem of bullying and harassment by management at the council-owned bus company.

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Unite said it had held off moving to a formal ballot to give the company time to rethink its attitude, but talks at the Advisory Conciliation and Arbitration Service had broken down. The union blamed a failure by management to seriously consider implementing measures to improve the workplace culture.

And Unite said it was now calling for an independent review into bullying and harassment by Lothian Buses management.

Unite regional industrial officer, Lyn Turner, said: “Unite has tried repeatedly to engage Lothian Buses management to address these important issues.

“We entered into talks at ACAS with a view to mutually agreeing a number of remedial measures, which we believed could find a resolution to this dispute. But, time and time again, Lothian Buses management have refused to seriously engage with us which resulted in the talks collapsing.

“Unite has until now not moved forward with a ballot despite being given a mandate by 94 per cent of our members showing support for industrial action in April.

“Lothian Buses have an opportunity to resolve this before the end of the ballot, which we are confident will show overwhelmingly support strike action.

“If they do not, then the public of Edinburgh and its politicians will have to ask serious questions as to why Lothian Buses seem hell-bent on engineering industrial action during the month of August when the Fringe and International Festival is on. This will only bring widespread disruption to the city but in those circumstances there will be only one party to blame.”

In response Lothian Buses blamed the union for the failure of the talks and accused them of failing to engage constructively.

A company spokeswoman said: “We are hugely disappointed that once again Unite have decided to use the media to communicate messages about this ballot.

“Unfortunately recent reconciliation talks proposed by Lothian and facilitated through ACAS broke down when Unite refused to engage in constructive dialogue and left the talks.

“We are hugely frustrated that the union leadership would ask its hard-working members to go on strike at a time when visitors from across the world are descending upon Edinburgh.