The former Conservative Party deputy chairman and international bestselling novelist has acknowledged that polls currently suggest Scots are ready to break away from the UK.
And he believes a second referendum is on the cards despite a similar vote in 2014 that resulted in a majority of Scots choosing to remain.
Archer said: “It’s going to be very interesting to see what happens in May if Nicola Sturgeon gets a big majority and whether she says that gives her the authority to have another poll.
“I’m torn. If the Scottish people give her a large majority and almost 60 per cent of them want independence, I would be very disappointed but I wouldn’t be against them having the right to test it. The world has changed beyond recognition.”
The 80-year-old said that, while he doesn’t expect to live to see independence for Scotland, it will inevitably happen.
But he also insisted the First Minister might not last that long in office, having already had more than six years.
He said: “I don’t expect to see it in my lifetime but I think you’ll see an independent Scotland at some time. I just don’t know when. Nicola Sturgeon is a very shrewd politician, extremely able. It’s whether she can last.
“One of the problems with politics, as Margaret Thatcher found out, is that there is a time limit whoever you are. And she has been there a long time.
“I think she’ll get through to the next election safely enough – by that, I mean in May – and if she gets her chance to do the independent thing, she’ll stay until then.
“But I suspect her days are numbered in the sense that nobody can survive beyond 10 or 11 years. Even Angela Merkel, who I am a huge fan of, has decided to go.”
Archer also revealed a little-known and unlikely friendship with former Labour leader John Smith, who died of a heart attack in 1994. The shock death came after many had predicted Smith was on course to become PM.
Archer said: “John was business secretary when he had just had the first of his heart attacks in 1988.
“I was on a tour of Scotland for the party so I rang the matron at the hospital and said, ‘I’d love to come and see him but I, of course, understand if he thinks it’s not quite right.’
“He called me up a few minutes later and said, ‘Come in here, Jeffrey.’
“I went into the hospital and sat on the end of the bed and we spent an hour chatting. The thing I most remember is that he said, ‘You’ve got to keep your eye on a man called Tony Blair and you’ve got to keep your eye on a man called Gordon Brown. I’ve stolen them. They’re both in my shadow business team and I can tell you one of them will be prime minister.’
“That couldn’t happen nowadays. A Tory MP wouldn’t sit on the end of a Scottish Labour MP’s bed while he’s in hospital, having a general pleasant chat. The second heart attack came later and, unfortunately, he died. But I look upon John Smith as one of the most decent men I’ve ever met in my life and I think he would have made a very good prime minister.
“He was very much for Blair and Brown. He thought they were the up-and-coming stars in the Labour Party. He said, ‘Keep your eye on those two, Jeffrey, because they’ll be after you.’
“The very fact that he chose both of them all those years back and chose very well proved to me years later that he would have had a very strong Cabinet and would have made a very strong PM.”
Archer – his full title is Baron Archer of Weston-super-Mare – was himself once tipped as a possible PM.
But his political aspirations came to an end in 2001 when he was jailed for four years for perjury and perverting the course of justice.
While in prison, he penned his prison diaries which – like his fiction – topped the bestselling charts.
These days he devotes himself to writing and his novels have sold 300million copies since his 1974 debut Not a Penny More, Not a Penny Less – which he wrote to avoid bankruptcy.
He received an advance of £3000 and only sold 3000 hardback copies but the follow-up, Kane and Abel, made him a fortune.
The first of dozens of his international bestsellers, it sold more than a million copies in its first week and became one of the most successful novels in history.
His latest novel Hidden In Plain Sight, which he will discuss with Ruth Wishart at a special Edinburgh International Book Festival event on Wednesday, is part of a planned series that follows a police officer through the ranks of the Met over several decades.
Former Prime MInister Tony Blair being interviewed in 1997 by Bill Heaney, editor of The Democraqt, during a visit to Allied Distilers in Dumbarton. Picture by Brian Averell
The author took Smith’s advice and kept an eye on Blair and Brown as they both rose to power.
He added: “I have got to say about Blair, you only have to raise his name at the Labour Party conference and they start booing.
“Don’t they remember he won three elections in a row? He was a winner. He took the Labour Party to victory.
“He beat the Conservatives by vast majorities.
“I think there’s a group of people in Labour Party who don’t like winning.Thatcher was full of admiration for the fact he won three in a row.”