It is the largest-ever closure plan by the company and will radically change the face of the bank, according to Unite.
Animals Help Hunt For Lottery Winner
The hunt is on to find the owner of a winning lottery ticket, who is yet to claim £3 million in prize money.
The search for the mystery winner was taken to Blair Drummond Safari Park near Stirling - the area where the ticket was bought for the draw more than five months ago.
Visitors at the attraction found the animals walking around a giant gold £3m figure in their enclosures today as part of a final push by lottery bosses to find the oblivious millionaire, who is sitting on a £3,062,272 fortune.
The unclaimed money is from the Wednesday December 17 draw when five numbers and the bonus ball were matched in the Lotto Quadruple Rollover. The winning numbers on that date were 2, 19, 24, 33, 35, 46 and the bonus ball was 12.
The owner of the winning ticket, which was purchased in the Stirling Council area, only has until June 15 to claim the prize.
A National Lottery spokesman said: ''We've been searching for this missing winner for five months now but, as yet, we've had no luck. With the ticket expiry date looming we're giving it one final push to find the mystery millionaire as, while there is still time, there is still definitely hope.
''Considering that going on safari is one of the top things on lottery winners' bucket lists, partnering up with Blair Drummond Safari Park was a natural fit. We hope this activity will help jog people's memories, as someone who bought their ticket in Stirling could be heading off on a luxury safari or another adventure of a lifetime if they claim in time.''
Lotto can only roll over four times and as no one matched all six numbers in the draw on December 17, the prize money was shared between the winners in the next winning prize level, with five winners sharing a total of £15,311,360.
If no-one comes forward with the winning ticket before the deadline, then the prize money, plus all the interest it has generated, will go to help National Lottery-funded projects across the UK.
The SNP claims a "Hard Brexit" will cost 80,000 jobs in Scotland.
A bullet has been recovered from a tree where a man was shot near a primary school.
Scotland's jobless total rose by 11,000 in the three months to November.
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