So says the UK government's Justice Secretary Elizabeth Truss 19 Feb
Truss was this morning interviewed on the BBC's Andrew Marr Show and was speaking in response to recent comments that some EU leaders think the UK can still change its mind. A legal challenge to determine whether the Brexit process can be reversed has been filed with an Irish court.
"People can take cases to court. My understanding is that it its irrevocable and when we press the button that will go forward."
Elsewhere Reuters report a Brussels source agreeing that optioin for the UK to change its mind has gone
"This bus has left. No one is happy about it but we have moved on and the last thing anyone wants now is to reopen the whole issue."
While the Irish minister for European issue Dara Murphy has told a forum:
"We have to accept the decision that Brexit will happen"
It's not going to stop people trying to reverse the decision though and the UK's own saga will continue for years to come.