Lorries will be parked at a disused airport in Kent the event of post-Brexit delays at the cross-Channel ports, the government has said.
The moves comes after MP Michael Gove warned queues of 7,000 trucks could clog up roads around ports.
A deal has been signed to use Manston as a lorry facility after the end of the transition period on 31 December, the Department for Transport said.
The M26 has been discounted as a lorry holding area, a spokeswoman confirmed.
The government has bought a 27-acre site near Ashford to provide a holding space for about 2,000 lorries.
It plans to deal with disruption at the Port of Dover and Eurotunnel terminal in Folkestone include the implementation of a contraflow on the M20.
When Operation Brock is in place, one carriageway of the M20 in Kent is used only by HGVs heading to cross-Channel ports, with all other traffic restricted to a contraflow system on the opposite carriageway.