Workers at dozens of Driving and Vehicle Licensing Agency (DVLA) offices will stage a 24-hour strike today in a dispute over closures and job losses.
Members of the Public and Commercial Services union at 39 local and 10 enforcement offices in England, Scotland and Wales will take part in the industrial action.
The union is campaigning against planned office closures, including those at Leeds, Sheffield, Lincoln and Beverley, arguing it signals the end of a "highly prized" face-to-face service to motorists.
The union has delivered a 72,000 name petition opposing the closures, to the Department for Transport, saying it was the largest paper petition it had ever organised.
Motorists will continue to be able to buy tax discs and apply for driving licenses at Post Offices after the Government announced a new contract between Post Office Ltd and the DVLA.
Transport Secretary Patrick McLoughlin today revealed the Driver and Vehicle Licensing Agency will award Post Office Ltd a new seven-year contract that will "build on the existing counter operation to provide a wider range of services and better accessibility for motorists".
The deal has been welcomed by one North Yorkshire MP who said local post offices and constituents had been "very concerned" the service could be lost.
Julian Sturdy, who represents York Outer, added: "I am very pleased that vital services will remain available in local communities."
Staff who work for the Driver and Vehicle Licensing Agency (DVLA) are walking out across our region today.
It is in protests to threats to close 39 offices. 1,200 people who work in the DVLA's local and enforcement offices will go on strike for two hours. It is part of action across the Department for Transport, who are taking industrial action against cuts to pensions, jobs and pay.
Unions claims the DVLA closures will put jobs at risk, but also put an end to face-to-face services the offices provide, which cannot be dealt with online or by telephone.