FILE PHOTO - Lorries are backed up on the M20 motorway which leads from London to the Channel Tunnel terminal at Ashford and the Ferry Terminal at Dover, June 23, 2015. REUTERS/Peter Nicholls

LONDON (Reuters) - Britain will hold a trial run on Monday of its plans for dealing with long queues of lorries at the southeastern port of Dover caused by disruption to cross-Channel traffic in the event of a no-deal Brexit.

The test will involve 150 trucks driving between a disused local airport, which will be used as a lorry park, and Dover to see if they clog up the road network.

With less than three months until Britain leaves the European Union, Prime Minister Theresa May is yet to win parliament’s backing for her Brexit deal and the government has stepped up preparations for the risk of leaving without a deal.

Dover is Britain’s main gateway to Europe, with up to 16,000 trucks a day passing through to the French port Calais at peak times, transporting everything from perishable food to medicines and industrial goods needed to keep factories running.

If it becomes blocked up by customs checks, tailbacks of lorries would quickly form on roads leading to Dover. Under the government’s plans, known as Operation Brock, Manston airport some 20 miles (32 km)to the north and parts of two motorways could become lorry parks.

“We do not want or expect a no-deal scenario and continue to work hard to deliver a deal with the EU. However, it is the duty of a responsible government to continue to prepare for all eventualities and contingencies, including a possible no deal,” a spokeswoman for the Department for Transport said.

“We will be testing part of Operation Brock to ensure that, if it needs to be implemented, the system is fully functional.”