It is the largest-ever closure plan by the company and will radically change the face of the bank, according to Unite.
Pro-Independence Campaigners Protest At Tunnock's
Pro-independence activists staged a brief protest outside the Tunnock's factory a week after the firm advertised its best-selling biscuit as the Great British Tea Cake.
Tunnock's has been accused of severing its Scottish roots with the launch of its latest marketing campaign in England.
Three people from the Scottish Resistance group, led by activist Sean Clerkin, stood outside the factory building in Uddingston, South Lanarkshire, with a lion rampant flag and handed out tea cakes made by rival Scottish firm Lees.
They were met by heckles from members of the public and from biscuit workers arriving for their shift.
Managing director Boyd Tunnock is a Conservative voter and spoke out in favour of the Union during the 2014 referendum debate.
He said the London Underground advert did not signify a re-branding of the popular treat and was simply a nod to the hit BBC show the Great British Bake Off.
The family firm established in 1890 sells about 3.5 million tea cakes a week.
Veteran anti-poverty campaigner Mr Clerkin said: "In Scotland today we have 970,000 people living in relative poverty, we have one in four children living in poverty, and what we are saying is that people like him, who are multi-millionaires, and supporting the Tories as they do, are helping to keep Scots in poverty.''
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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