Driving examiners are planning a further series of strike action next week.
PCS has planned regional action at various times from Tuesday 1 December until Friday 4 December 2015 where a national walk out is planned.
Meanwhile, Prospect union is planning to take strike action every Friday, starting from starting from Friday 27 November 2015.
The union accused the Driver and Vehicle Standards Agency (DVSA) of putting road safety at risk by planning to increase the number of driving tests allowed in a day. PCS added that this could breach the legal requirement for elements of the test to be conducted in "good daylight".
In two separate votes, 91.5% of PCS members voted for strikes and 96.9% for non-strike industrial action (such as work-to-rule) on a 64.6% turnout. As a result, test centres have already faced disruption with a two-day strike last week (19-20 November 2015).
The unions said they had written to the permanent secretary of the Department for Transport Philip Rutnam asking him to intervene and to instruct his management team to negotiate in good faith. PCS and Prospect have also lodged an Early Day Motion and said they would “will ensure that the employer’s appalling approach is raised in Parliament”.
DVSA said staff had signed up to a new standard employment contract in April 2014 in exchange for a lump-sum payment and a three-year pay deal. This was agreed with the trade unions, and applies to all staff in the Department for Transport and motoring agencies. The pay deal included transitional arrangements that came to an end on 1 November 2015.
The agency said it was doing all it could to make sure that tests go ahead as planned and added that it expected most driving test centres to operate as normal and that test candidates should turn up for their test as planned.
Paul Satoor, DVSA’s interim chief executive, said: “We’re doing everything we can to minimise any disruption to customers and we apologise for any inconvenience.
“It’s disappointing that the trade unions have now chosen to oppose the contract they agreed in 2014.”