The protest will take place outside the headquarters of the DfT, Great Minster House, London as the DfT board decide on whether to recommend the privatisation of VOSA to the Secretary of State.

VOSA is responsible for checking the safety of heavy goods vehicles, public service vehicles and the monitoring of MOT garages. The unions fear that a move to outsource the functions of VOSA would threaten the integrity and independence of the inspection regime and go against the government’s stated objectives on road safety.

VOSA’s own estimates, based on its duty to monitor private garages undertaking MOT testing, show that 15 % of all car MOTs delivered by the private sector each year are deficient - against a percentage of deficient lorry MOTs delivered by VOSA of 0.09%, or 0.03%.for buses.

The unions, which represent 2,650 people working for VOSA, are urging the board of DfT to consider the whole of the business plan for the privatisation which they believe is seriously flawed and contradictory.

Prospect general secretary Paul Noon said: “After Railtrack and Metronet it seems inconceivable that anyone could still believe public-private partnerships and transport are a good mix. Yet some VOSA functions, including HGV and public service vehicle testing, remain under the threat of privatisation. Our members believe that the largest and heaviest vehicles on the road should be examined by an organisation focused purely on safety and without any restrictions imposed by the need to return a profit.”

Commenting, David Millar, PCS negotiations officer for VOSA, said: “The plans to outsource work are flawed and will compromise road safety. Not only would these plans threaten the integrity and independence of the inspection regime, but they would also undermine the government’s targets on road safety. The DfT board should take the chance to throw out these damaging proposals.”

Unite regional officer, Jerry Pickford said: “This is another example of the government’s continuing policy of privatisation of the public sector. Expensive consultants have been brought in, not to look at how the agency can be improved, but to see how it can be handed over to the private sector, more interested in making profit than ensuring public safety.”