A dress rehearsal to test the government's plan to use the Manston airport site as an emergency lorry park is underway - but questions are already being asked about its value.

The trial began at 8am but there were reports that fewer than 90 of the 150 HGVs expected to participate had turned up.

The first phase of the dry run saw lorries sent on their way in groups of 10 to Dover from the airport site.

Hauliers themselves have questioned what value there is in the exercise with numbers lower than anticipated.

Rod Mackenzie, of the Road Haulage Association, tweeted: "#NoDealBrexit planning at #Manston today is window dressing - at least nine months too late to be effective and with so few trucks involved."

Dover MP Charlie Elphicke tweeted that using Manston is not the answer.

He said: "Routing lorries via Manston is not the answer. Far better to extend the tried and tested traffic management system on the A20 at Dover to Kent’s motorways.

"That way lorries can be effectively managed, got most speedily to the ports and all our motorways can be kept open.

"Manston should only be used as a last resort. The speed lorries can be got down to the port is too slow.

"Trying to explain to lorry drivers - many from overseas - to go there will be very difficult. The whole route plan is far to complex and will cause enormous confusion.

"Better to stick to what lorry drivers are most used go - going to the Channel Ports via the M20/A20. Yet using traffic management to keep the motorways open and use Manston only after road capacity is used up."

KCC has previously warned that a no-deal Brexit could see the county's road network having to hold as many as 10,000 lorries on a routine basis.

Ruth Bailey, chairman of Manston Supporters group, tweeted: "Do 83 lorries constitute any thing like a real test?

"Surely this is no more than a PR exercise for a Government that is in complete shambles."

Anti-Brexit Labour MP Stephen Doughty added: "This is yet more extraordinary incompetence from this shambolic government."

However, the DfT says the first roll out of lorries went well.

The DfT had hoped 150 trucks would take part in Monday’s test, .

“This is designed to test what happens if there is no deal and Operation Brock is implemented,” said a spokesman referring to the codename for the Brexit traffic management plan.

MP for North Thanet, Sir Roger Gale, said: "The Road Haulage Association has already described it as window dressing and I fear that is what it is.

"I am all in favour of having an exercise but lorries leaving on a pre-planned basis with the public knowing when it is going to happen is not by anyone's standing a real or sensible exercise - there has been a lot of warnings which is why people have used other routes instead of the roads the lorries were on. That is not a sensible exercise."