Historic TV debate will be 'meaningless' to Scots

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The first debate, to be broadcast on ITV, will focus entirely on "domestic affairs", with foreign affairs and the economy to take centre stage at subsequent Sky and BBC debates.

While some domestic issues – such as immigration and political reform –will apply to Scotland, areas such as education, health and policing are now run entirely by the Scottish Parliament. Gordon Brown, David Cameron and Nick Clegg are therefore likely to focus on policies exclusively for south of the Border.

Mr Salmond said the broadcasters had ensured Scotland's voice was not being heard at the debates, which are likely to be watched by millions across the UK.

But his claim the debates would be "meaningless" was slated by Labour, which said that much of tomorrow's event would still have significant relevance to Scotland.

With the SNP angry over its exclusion, Mr Salmond has stepped up the pressure on the BBC and is demanding a face-to-face meeting with corporation bosses.

The SNP claims the BBC is breaking both communications law and its own guidelines on impartiality by agreeing to broadcast its debate in Scotland, without one of the main Scottish parties being represented.

The three debates, to be screened in each of the next three weeks, are set to be the key events in this year's campaign.

Mr Brown, Mr Cameron and Mr Clegg are expected to take a break from campaigning today as they are "prepped" by their parties. The experience of the US presidential debates has shown a close election can be won or lost on the strength of a candidate's performance.

But the debates have caused controversy in Scotland, as no SNP representative will be able to have their say. The Nationalists say that, as they are defined as a main party in Scotland, the broadcasters are breaking the rules on impartiality.

Mr Salmond said tomorrow's debate was not only unfair but also largely immaterial to Scots. "Broadcasters sometimes trail their programmes by saying they can be seen 'except for viewers in Scotland'. In the same way, this leaders' debate is being directed at the electorate – except for viewers in Scotland," he said.

"The so-called domestic issues which will be debated – things like health, education and policing – are all controlled in Scotland by Holyrood. As such, this discussion will be totally meaningless to viewers in Scotland."

The SNP and Plaid Cymru have written again to the BBC Trust, asking for an oral hearing to oppose the BBC's decision not to have an SNP representative at its debate, to be screened on 29 April.

The letter, seen by The Scotsman, notes that the decisions made this year by the broadcasters will set a precedent, with TV debates likely to become a regular fixture at election time.

It adds: "There can be few issues as important to the BBC, the BBC Trust and the political parties as the fair and impartial coverage of a General Election. It goes to the heart of the functioning of our democracy and the concepts which underpin public broadcasting."

The BBC Trust is still considering the request.

Bookmakers yesterday were offering odds of 4/5 on David Cameron "winning" tomorrow's debate. They put Gordon Brown at 15/8 and Nick Clegg at 11/4.

However, there is a growing belief in Labour's campaign HQ that Mr Brown may benefit, both by appearing as a contrast to his two younger rivals and because the expectations of him putting in good performance are low.

Both he and Mr Cameron have already hired American political consultants who have prepared presidential contenders for their own debates in the past.

In a television interview today, Mr Brown admits he is "not so good" at the presentational side of politics. He says he is not a "personality" who tells people what they want to hear.

PRECIOUS TIME

ALEX Salmond has told Scots they could be wasting their time watching tomorrow night's leaders' debate. So here are some suggestions on how to fill the time:

Head up a hill, preferably somewhere without mobile phone reception, avoiding Twitter/Facebook updates

Book an overseas holiday for the week of the election

Test out the new rules of Scrabble and try not to fall out without your partner

Take in a real intellectual debate, charting 20 years of Scottish theatre at the National Library of Scotland

Watch the live darts on Sky Sports and imagine your least favourite leader is pinned to the board

Hide inside the "sonic dreams" capsule, which is in the capital for the Science Festival

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Historic TV debate will be 'meaningless' to Scots – SNP