The ticket was bought in the run-up to the superdraw on Wednesday September 18 and is the largest Lotto jackpot to remain unclaimed for so long.

Winning numbers

37, 12, 07, 04, 29 and 42

National Lottery operator Camelot said the money had already generated nearly £15,000 in interest.

The deadline for claiming the prize is 11pm on 17 March next year.

In total nine National Lottery players have failed to collect their jackpot prizes, which amount to more than £17m.

Ticket holders have 180 days to pick up their winnings before the money, together with any interest generated, goes to the six designated good causes.

In 2001, the case of Martyn and Kay Tott, from Watford, won the support of then culture secretary Chris Smith after Camelot said they had missed the 30-day deadline for claiming lost tickets.

Camelot put the couple through seven weeks of waiting before apologising, but insisted it could not break the rules despite a £3m jackpot being at stake.