British Prime Minister David Cameron made an impassioned speech to the people of Scotland today, warning that their referendum decision on independence Thursday will be "forever" and urging them to consider their "children, grandchildren and the generations beyond."

He promised that if the Scots reject independence, they will immediately get new powers for their existing Scottish government, including "major new powers over tax, spending, welfare services."

"If you don't like me, I won't be here for ever. … We don't need to tear our country apart," he said.

"Please, please, don’t let anyone tell you you can't be a proud Scot and a proud Briton."

He stiffened his impassioned speech with a warning that separation would be painful, including losing the British currency, maintaining separate armed forces, pensions to be sliced up "at some cost," and no support for international travellers.

He was speaking at a televised gathering in Aberdeen. The slogan on the lectern and on the screen behind him said, "Let's stick together."

On Sunday, Queen Elizabeth made her first comments about this week's independence vote, urging Scots to "think very carefully about the future." But the popular monarch didn't indicate a preference on how Scots should vote, carefully maintaining the neutrality that is her constitutional obligation.

Scots are to vote Thursday on a simple, six-word question: "Should Scotland be an independent country?" The options are simply Yes or No.

Scottish First Minister Alex Salmond gives the thumbs up. His campaign for a Yes vote appears to be gaining. (Andrew Milligan/Associated Press)

Opinion polls have narrowed as the vote nears, adding to the suspense.

While the Queen has been careful not to betray her own opinion, some may interpret her comments as a suggestion that Scots looking to embrace independence should be cautious about severing Scotland's long ties to the United Kingdom, which date back more than 300 years.

She spoke after a Sunday church service near her Balmoral estate in Scotland. She made the comment to a well-wisher in the crowd.

Buckingham Palace recently issued a statement indicating her plan to remain neutral before Thursday's vote.

Across Scotland, meanwhile, dinner table talk is getting heated as families fight over how to vote in Scotland's independence referendum. A generation gap has opened up, with younger voters more inclined to back independence and their elders tending to say they want to remain in the United Kingdom.

Queen Elizabeth has said she will stay out of the independence debate despite calls for her to intervene. (Russell Cheyne/Reuters)

Support for the status quo is strongest among the over-60s, who are worried about the consequences breaking free would have on pensions, health-care and savings; the pro-independence movement is largely being driven by under-40s. Neck-and-neck in the polls, the rival campaigns have called on core supporters to make a last ditch attempt to swing the vote by making the debate a family affair.

The young are being urged to visit parents and grandparents to explain why they should support separation. The No camp has launched a counteroffensive by asking seniors to win young hearts and minds with their wisdom.

"I was so proud of my grandpa when he told me he was voting Yes that I burst into tears," said Miriam Brett, 23, from Shetland and a campaigner for Generation Yes.

"A Yes vote means so much to my generation. We want to let all our grandparents know that their future is secure in our hands, and with a Yes we can build a better future for ourselves and for our children."

A message supporting the Yes vote in the Scottish referendum on a mountain in West Belfast, Northern Ireland. (Peter Morrison/Associated Press)

The No camp is trailing in every age group except the over-60s. Polls indicate more than 63 per cent of that age group is expected to vote in favour of the union. As older people are more likely to be on the electoral roll, there has been a huge drive to get younger people engaged in the Yes campaign.

Interest in the referendum is sky high. A total of 4,285,323 people, representing 97 per cent of the population, have registered to vote in the referendum. That's an increase of 300,000 on those registered in Scotland in 2012.

Teenage voters

The turnout for Thursday's ballot could exceed 85 per cent, compared to just 50.4 per cent who voted in the last Scottish Parliament elections in 2011, and the 63.8 per cent who turned out for the 2010 UK election.

Among the electorate are 124,000 voters aged 16 and 17 who have been granted the right to vote for the first time. Many of these new voters are expected to support independence. But conventional wisdom holds that older voters are more likely to actually cast their ballots, a factor that could help the "Better Together" campaign.

First Minister Alex Salmond described the Generation Yes campaign as "inspired" and said young voters now have a great excuse to pop around their grandparents' house for a traditional Sunday lunch.

However with polls suggesting as many as 40 per cent of families are divided over the referendum — and at least 20 per cent saying the debate has led to heated family arguments — the art of friendly persuasion has not exactly been easy.

"My Dad stopped talking to me when I said I was going to vote Yes," said 21-year-old student Laura Brown. "He even blocked me as a friend on Facebook."

Gordon Brown

The "Better Together" camp says older voters have a wealth of experience to impart on younger ones.

"Scotland's one million pensioners should use their vote and their voice to remind their children and grandchildren of how the NHS and pensions were secured by the power of working together," said former British Prime Minister Gordon Brown, a major figure in the Better Together effort.

"I urge you to use both your vote and your voice to remind your children and grandchildren of suffering endured together, sacrifices made together and achievements earned together with friends, neighbors and relatives in England, Wales and Northern Ireland," Brown said. "Tell them how we fought and won two world wars together."

It's a message that resonates with older voters who worry that younger generation might be making a mistake.

"They haven't lived long enough to see what we have," said Liz Mullen, 68, a retired office worker from Paisley. "A lot of young people think independence is going to be some sort of miracle cure …. They think it is some kind of adventure without any risks, but this is not a video game."