Unless the winner of a major National Lottery prize opts to take full publicity and signs an agreement to that effect, no further information can be released about their win.
A National Lottery spokesperson said: “We’re delighted that the winner of this amazing prize has now come forward and we hope that they will enjoy their win.
“It would have been awful if the ticket-holder had missed out on this substantial and life-changing amount of money.
“We would like to remind all National Lottery players to check their tickets every time they play.”
Winners have 180 days from the date of the draw to claim their prize or the money will go to good causes.