PEOPLE-smugglers sparked a stampede of illegal immigrants trying to enter Britain over Christmas by claiming the UK will close after Brexit.
The warning emerged as figures revealed the number making the perilous Channel crossing has rocketed by 400 per cent in the past year.
French officials said 2,358 were saved trying to make the journey on small boats or by swimming in 2019, up from 586 in 2018.
Sixty were rescued on Boxing Day, while 43 including eight kids were found off the coast of Dover on New Years Eve.
But just 125 migrants who tried to slip into Britain unseen on dinghies in 2019 were sent back to Europe.
Immigration Service Union general secretary Lucy Moreton said the numbers are rocketing as trafficking gangs try to use Brexit as a twisted marketing ploy.
She said: One of the drivers we are being told is that people smugglers are telling these folk that after Brexit Britain will close in some way.
Brexit doesnt make a difference, but we do know that the criminals are using this to try to drive more business.
She said Britain saw similar spikes just before the March and October Brexit deadlines.
Traffickers charge migrants between 6,000 and 10,000 to take them across the Channel and coach them in what to say to try to claim asylum.
But Ms Moreton warned some are attempting the journey solo with one found in the water in flippers and with a float, while another pair were found in a kayak.
Dovers new Tory MP Natalie Elphicke demanded a fresh approach to tackling the rise in migrants crossing the Channel.
She said: Traffickers will say and do anything to drum up business. It is the job of the French and British authorities to stop them.
Thats why there needs to be a fresh approach where the British and French authorities jointly agree that anyone picked up in the Channel is returned to the safety of France and not brought into Britain.
This would be the surest deterrent and the most compassionate thing to do.