Alistair Darling makes Alex Salmond Kim Jong-il jibe
The leader of the pro-union Better Together campaign has compared Alex Salmond to former North Korean dictator Kim Jong-il.
In a New Statesman interview, Alistair Darling said the Scottish first minister's criticism of UKIP television coverage was a "North Korean response".
A spokesman for Mr Salmond said the remarks were pathetic and puerile and called for an apology.
Better Together said the reaction to the article was "overblown".
A Better Together spokesman said that the Kim Jong-il comments were poking fun at the first minister's comments blaming the rise of UKIP in Scotland on the BBC's coverage before the European elections.
In an interview with the New Statesman editor Jason Cowley, the former Labour chancellor of the exchequer was quoted as saying: "He (Alex Salmond) said on the BBC that people voted UKIP in Scotland because English TV was being beamed into Scotland.
"This was a North Korean response. This is something that Kim Jong-il would say. And this is the same BBC for which we all pay our licence fee, and we all enjoy the national output as well as the Scottish output."
Kim Jong-il, who became the communist dictator of North Korea in 1994, presided over one of the world's most reclusive and oppressive societies until his death in 2011.
He was accused of severe human rights abuses, and of threatening the stability of the region by pursuing a nuclear weapons programme and testing long-range missiles.
Responding to Mr Darling's comments, the first minister's spokesman said: "Alistair Darling demeans himself and his colleagues in the No campaign with these pathetic, puerile remarks for which he should now apologise.
"The debate on Scotland's future is one that deserves far, far better than boorish and abusive personal insults, as do the people of Scotland.
"Mr Darling has called for a positive debate free from abuse - he should now aim to live up to that pledge, and stop trying to divert attention from the real issues."
On Mr Darling's language, the Better Together spokesman said: "The nationalists have regularly dismissed people who don't agree with them as quislings, anti-Scottish and a parcel o' rogues.
"We won't take any lessons on the use of language from people who have such a proud record of slurs and personal attacks."
After the UKIP victory in the European elections, Mr Salmond had stressed that UKIP received significantly less backing north of the border, despite gaining an MEP.
He said: "It's difficult it is to stop a party getting foothold. We've been doing an analysis of BBC broadcasting in Scotland over this month, four-times as many broadcasts about UKIP than the SNP."
Mr Salmond told the BBC's election night programme: "Star Trek the Original series used to have a phrase, 'beam me up Scotty', UKIP is a party that gets beamed into Scotland courtesy of the BBC."
In the New Statesman interview, Mr Darling had originally been quoted as using the controversial phrase "blood-and-soil" about Scottish nationalism.
The magazine later admitted the phrase had been used by the interviewer and issued a clarification, blaming a transcription error. A correction appeared online but the magazine has already gone to print.
The expression "blood-and-soil" ('Blut und Boden') is German in origin and became a term associated with the Nazis.