Scotland's First Minister Alex Salmond has been urged to apologise after using a term linked to officials in Nazi Germany to describe a BBC adviser.

The SNP leadercriticised the corporation after his planned appearance on a sport show ahead of yesterday's Six Nations Scotland-England rugby clash was cancelled on political grounds.

Mr Salmond suggested BBC journalists were "in thrall to Downing Street" and likened it to "tin-pot dictatorships".

He also compared one of the corporation's advisers to a Gauleiter, the term given to provincial governors in Germany under Hitler. It also means someone in authority who behaves in an overbearing manner.

Scottish Labour called it an "ugly smear" while the Scottish Tories described it as "bully-boy tactics".

Mr Salmond had been due to speak about rugby and give his predictions for the first three Six Nations matches.

He told the Sunday Herald that it was all settled but then the BBC adviser, "the political Gauleiter we should call him now, intervened to say this shouldn't happen and, really, he's lost the plot".

He said he imagined people like the adviser "are in thrall to Downing Street now and that is actually the worrying thing. What this means is that an editorial decision, a journalistic decision on the BBC by the sports editor, has been overridden for political reasons by the political advisers.

"That's what you get in tin-pot dictatorships, You're not meant to get it in the BBC."

Scottish Labour called on Mr Salmond to apologise and withdraw his use of the term "Gauleiter".

Its external affairs spokeswoman Patricia Ferguson MSP said: "People want the First Minister to get behind the team, not get on television.

"What is totally unacceptable, however, is for the First Minister to accuse journalists of occupying the post of a Nazi district leader. That is an ugly smear.

"Maybe he doesn't understand quite how offensive that term is, in which case he should withdraw it today.

"But if he is familiar with what the term means, that is a far more serious breach of the standards expected of his high office and he must apologise for it."

Scottish Tory leader Ruth Davidson described it as "bully-boy tactics".

She said: "Now we have the First Minister himself using words like 'dictatorship' and 'Gauleiter' to attack a BBC official for daring to deny him his face on the television.

"It is a completely inappropriate outburst from a man supposed to be running Scotland, and symptomatic of the SNP's 'attack mode' where they try to destroy anyone with whom they disagree."

Scottish Liberal Democrat leader Willie Rennie called on Mr Salmond to "retract this slur on the integrity of the BBC".

A spokesman for Mr Salmond said: "The First Minister was rightly referring to over-officious BBC officials, and the real concerns about editorial decisions taken by BBC journalists being overruled by bureaucrats on political grounds.

"As the Sunday Herald copy says, 'the term has come to mean an overbearing bureaucrat'.

"That is unacceptable, and the First Minister will be raising the issue with Lord Patten, chairman of the BBC Trust, when he meets him in Edinburgh on Thursday.

"The First Minister didn't complain when he was compared on the BBC to Robert Mugabe, and the opposition parties' obsession with trying - and failing - to do down the SNP is clearly causing them to ignore the real issue of editorial independence."

While the TV appearance was being arranged, Scottish Government officials emailed BBC sport editor Carl Hicks to say Mr Salmond was "not looking in the slightest to make any kind of political or constitutional points" but the appearance offer was later withdrawn.

A BBC spokesman said: "The BBC's obligation is to ensure it achieves due impartiality across all its output.

"Given the nature of political debate around Scotland's future and the proximity of local government elections in Scotland, it was decided that it would be inappropriate to give undue prominence at the moment to any single political leader in the context of the Scotland-England game."