Image caption Chris and Colin Weir have rarely appeared in public since celebrating their lottery win in 2011

A couple who won £161m on the Euromillions lottery have called for an end to the "smears" which they said were blighting the Scottish independence debate.

Colin and Chris Weir are reported to have given £3m of their fortune to the SNP and Yes Scotland.

The couple said the donations had led to them being subjected to "downright nasty" personal attacks.

They called for both sides to respect opposing views ahead of the referendum.

In a letter to the Herald and Scotsman newspapers, Mr and Mrs Weir said they had made a decision not to speak publicly about any aspect of their lives when they won the Euromillions jackpot three years ago.

The couple, from Largs in Ayrshire, said they tried to live the same "quiet, decent, lives" just as they had done before their win.

They have used their fortune to fund several good causes, including buying a 13-year-old boy a prosthetic leg, and have established a charitable trust to help fund health, sport, cultural, recreational and animal welfare projects.

It is time for all sides to stop the smears and personal attacks before a line is crossed and attitudes adopted that cannot easily be healed Chris and Colin Weir

But they said their silence had "meant that, from time to time, we have been subjected to comment and speculation, the majority of it kind and generous, some of it mischievous or ill-informed and, occasionally, some of it downright nasty".

They said they trusted the public to "recognise the difference between fact, speculation and idle gossip".

The couple added: "We appreciate that not everyone shares our political view. That surely is the point of democracy. And, in a democracy, we each have the right to support political campaigns of our choosing and to contribute financially, provided we do so in line with the rules.

"As lifelong supporters of independence, it would be strange if we did not support the Yes Scotland campaign. So that is what we have done, nothing more and nothing less.

"No-one bullied or targeted us, as has been suggested in recent newspaper articles. The only 'targeting' has been by an MSP who chose to express his 'concern' for us by implying we have been, at best, naive, and, at worst, duped. Would he, we wonder, have felt the same concern had our contribution supported his cause?"

Last month, Mr and Mrs Weir were the subjects of an article in the Scottish Daily Mail newspaper in which Tory MSP Alex Johnstone suggested the couple may have been "targeted" for donations.

'Honesty and integrity'

In their letter, the Weirs said that the people of Scotland would "all have to live together" regardless of the outcome of the referendum on 18 September, when voters will be asked the Yes/No question: "Should Scotland be an independent country?".

The Weirs said: "That will only be possible if both sides of the campaign, the politicians and the media take responsibility for their behaviour and language in the next few months.

"They are the ones who will steer Scotland through this challenging period - we can't have the possibility of leaving our country fragmented.

"So it is time for all sides to stop the smears and personal attacks before a line is crossed and attitudes adopted that cannot easily be healed. No-one - on any side - should be vilified for the views they hold, lest our democ­racy become the victim of the debate.

"Differences can and should be expressed - but decently, with honesty and integrity.

"Our lives have been blessed with good fortune. And we wish to live out our time in a happy and confident Scotland, one which respects and thrives on political differences. Other­wise, in a race to the bottom of the pol­i­ti­cal barrel, we will all be the losers."

A spokesman for the pro-independence Yes Scotland campaign said Mr and Mrs Weir deserved to be treated with "courtesy and respect".

The pro-UK Better Together campaign said "everybody should feel free to express their view without fear of abuse".