RMT members working for First South West will take strike action on August 9 and 12, after union bosses claimed the bus company refused to negotiate an end to the dispute.
The union said it put forward three different counter-proposals as a basis for negotiating a settlement to prevent further strike action and to bring both sides together.
A spokesperson for the RMT union said: “The counter-proposals were produced after holding extensive depot-by-depot consultations with our members who were determined to reject the company’s latest proposals.
“However, First South West not only ruled out discussing the union's proposals but went on the offensive in the media spinning falsehoods about RMT members.”
RMT general secretary Mick Lynch said: "Our members are furious with company MD Simon Goff for refusing to sit down with our negotiators to hammer out a deal and instead attempting to discredit the union in the media.
"First South West already have some of the poorest pay rates for bus workers in the region and have added insult to injury with ludicrous comments about their own staff.
"It is a viable business with a parent company boasting profits of £204-million so the idea RMT's counterproposals are unaffordable is laughable and bus workers know it.
"Industrial relations disputes are solved through dialogue between the union and employer, not childish rhetoric or producing fantasy figures to try to undermine our strike action.
"Our First South West members are now more determined than ever to take effective strike action on August 9 and 12 to hammer home the point to the employer that their vital service to the local community cannot be taken for granted."
In response, Simon Goff, First Bus South managing director (operator of buses of Somerset and Cornwall by Kernow), said: “We are disappointed that yet again, the RMT have refused to put our latest offer to the membership, instead choosing more unnecessary disruption to our passengers who rely on our services.
“We know that the RMT’s actions do not have the support of the membership. Our people are telling us they disagree with RMT action and are prepared to work during the strike. We can see this in the 83 per cent of staff in Somerset and over 50 per cent in Cornwall who turned up to work during the last strikes.
“Our full and final substantial offer of 5.1 per cent is above inflation offer for all pay grades, which follows a significant pay increase of 17.6 per cent in December 2022. The counter proposals the RMT are putting forward are simply unsustainable for the business and impossible to fulfil. We cannot agree to their demands, because these are totally unviable and will put bus services and jobs at risk.
“The RMT have had every opportunity to call off their action and put this offer to their membership. It’s totally within their gift to withdraw the planned action for this weekend.
“We know that many of our people would like to accept the offer. This is in the RMT’s hands now and they must let their members have their say.
“I’d like to personally thank our staff who simply want to see this resolved and have chosen to continue to work through the strikes to serve their local communities.”