Former Prime Minister Gordon Brown will today set out why he passionately believes Scotland should remain part of the UK.
The Labour MP is expected to speak about his deep sadness that the country is being polarised by nationalism and will urge Scots not to break the links with their neighbours south of the border.
Mr Brown believes an independent Scotland would be more socially unjust than it is at present given SNP plans to cut corporation tax and a refusal to increase the top rate of tax on high earners.
The 63-year-old said his main motivation for getting properly involved in the campaign was fears over the future he would leave his family and people he represented.
Mr Brown, MP for Kirkcaldy and Cowdenbeith who stood down as prime minister in 2010 after losing the general election, is attending the launch of Labour’s referendum campaign in Edinburgh today.
Speaking ahead of the launch, Scottish Labour leader Johann Lamont said: “In just over 100 days, the people of this country will come together to decide our future and we believe it is in Scotland’s interests to continue working in partnership with our neighbours.
“Scotland is already a nation with a strong parliament which has power over the things that really matter to people like schools, hospitals and jobs.
“But we believe it makes sense to share other things as part of a bigger country of 60million rather than just five, giving us the economic certainty and security we would want.”
Ms Lamont said the level of interest in attending a Labour rally in Glasgow tonight was testament of how passionate people felt about Labour’s vision for the UK.
“We will make our arguments and fight for every vote until September 18 because we believe Scotland’s best future is part of the UK,” she added.