THE voice was familiar even if the introduction was not.

Scotland's radio-listening public collectively choked on its porridge yesterday when breakfast time phone-in caller "Alex from Strichen" turned out to be none other than the First Minister.

Alex Salmond phoned BBC Radio Scotland's popular Morning Call show to berate councillors who had threatened to use recently expanded electoral rolls to pursue outstanding poll tax debts.

In the extraordinary 15 minutes that followed, he backed a contribution from fellow caller "George from Inverurie" and chatted cheerfully with "James from Sutherland". He also launched into a prolonged and withering cross-examination of Aberdeenshire Council leader Jim Gifford, whom he accused of "putting the frighteners" on people who added their names to the electoral register to vote in the independence referendum.

The exchanges began on a surreal note when host Kaye Adams told listeners: "You'll never guess who's phoned in.

"We have Alex from Peterhead. Good morning, Alex."

"Not from Peterhead, Kaye," said the well-known voice, "from Strichen in Aberdeenshire..."

"Good morning, First Minister, thanks for phoning in," said Ms Adams, nervously regaining her composure.

Mr Salmond, who is understood to have been calling from his Aberdeenshire home, wanted to join a discussion about plans he had unveiled the previous day to ban councils from pursuing poll tax debts dating back to the late 1980s and early 1990s.

He accepted his proposed legislation would have limited practical impact as most poll tax debts have been legally wiped out because they are more than 20 years old.

But he claimed councillors across Scotland - including Mr Gifford - had alarmed people by threatening to take action.

Accusing them of being "deeply cynical", he told listeners: "That's why the Scottish Government acted. Because politicians, any politician, shouldn't be allowed to put the frighteners on people."

Mr Gifford, a Conservative, might wish he had not phoned in to argue his case at that point, as he was subjected to a humiliating interrogation by Mr Salmond.

As the demolition continued, the First Minister pointed out that Mr Gifford had been elected to the council by just seven per cent of those eligible to vote.

"A ridiculous thing to bring up," objected the hapless council leader, who traded insults by suggesting the First Minister told SNP councillors what to think.

"Oh Jim, Jim. Dear, dear, dear," said the First Minister. "You don't like answering questions, but you are quite prepared to dish out insults."

The put-down delivered, he told Ms Adams: "I'd absolutely adore to stay on the programme but there are one or two other things I have to attend to."

The Scottish Conservatives yesterday raised fresh objections to Mr Salmond's proposed poll tax legislation, claiming it was unworkable.

They also said Mr Salmond had too much time on his hands.

Since announcing his decision to step down as First Minister next month, Mr Salmond has enjoyed a visit to the Ryder Cup and he appears to be taking a closer personal interest in the media.

He wrote a personal letter to The Herald last month in response to a piece by columnist David Torrance.

In it, Mr Salmond said that Mr Torrance, who wrote a highly regarded biography of the First Minister, "doesn't know me at all".

Meanwhile, he has been accused of leading a "zombie government" until his successor has been appointed.

Tory MSP Alex Johnstone said: "Alex Salmond's impromptu appearance on the show very much ties into the idea of a thumb-twiddling First Minister who simply has nothing better to do."

Ms Adams said: "It was a surprise to receive a call from the First Minister. We didn't expect it, but, as is the case with all of our callers, we appreciated his contribution. It's great Morning Call can bring everyone together to talk about the big issues."