A "world famous" Banksy mural that has been painted over could be restored, experts have said.
The artwork in Dover, which shows a star being chiselled from the EU flag, was whitewashed and feared destroyed.
The Fine Art Restoration Company, which has restored about a dozen Banksys, said it was "certainly reversible".
The building's owners have not commented on their plans for the mural and Dover District Council said it is "disappointed" it had been obscured.
Bansky, who rarely comments on his work, on Thursday said there were plans to update the piece on "Brexit day" to show a crumpled flag on the ground, but said it "seems they've painted over it".
Posting on Instagram, the elusive artist said the "white flag" that replaced it "says it just as well".
The former Castle Amusement site in Townwall Street is owned by arcade entrepreneurs the Godden family.
The owners have not told Dover District Council (DDC) what has happened to the mural, according to Edward Biggs, a Labour councillor for the area.
"Either it's been destroyed or, we are hoping, this is just a protective measure," he said.
He said "we are all very disappointed" it has been obscured, adding: "It was just a very apt illustration of what's going on. Dover is right on the forefront of Brexit."
Art dealer John Brandler, who has helped salvage other Banksy works, said he was hopeful it could be restored, adding: "The painting is still there."
Referring to the mural as having been destroyed was "like saying that a car is no good any more because it's got a dent in it," he said.
He added: "I would say this particular piece is one of his four of five most valuable works.
"It's world famous. It's got global attention, because everybody is talking about Brexit."
Chris Bull, of the Fine Art Restoration Company, said reversing the whitewash would be a "painstaking process" that may take months to achieve, due to the scale of the mural.
Restorers would take a sample of the "over paint" that could be analysed to see "exactly what it is made of", before determining which "solvents and chemicals are used to reverse it," Mr Bull said.
A DDC spokesman said: "We're disappointed to see that the Banksy mural appears to have been removed, recognising that this unique artwork had become a popular tourist attraction in the town."
The council "was not involved in the current activity, and was not made aware of any plans for it to take place," it said.