With Scotland set to cast an historic vote for independence next year, campaigners battling to keep the country part of the United Kingdom sought advice from former Canadian prime minister Jean Chretien, a man who knows a thing or two about fighting referendum campaigns.

Scotland has been a part of the United Kingdom for more than 300 years, but many have long believed that the constituent country would be better off economically and socially as an independent sovereign state.

The issue solidified last year with the announcement of a referendum scheduled for Sept. 18, 2014. Some 4 million Scottish voters will be asked the simple question, “Should Scotland become an independent country?”

As Scots on both sides of the debate gear up for a lengthy campaign, British government leaders against separation invited Chretien to London this week to share his experiences during the 1980 and 1995 Quebec referendums.

Although Chretien did not offer a specific opinion on Scotland’s future, he told a meeting of British MPs and business people that being on the “no” side means breaking the dreams of those who want independence, which isn’t always easy.

A referendum can divide families, towns and cities, he added.

Chretien did praise the short and clear referendum question for its eight-word simplicity and the phrasing of “an independent country.”

“That could not be clearer,” he said.

Pro-independence forces have struggled in the early stages of the campaign. The ruling Scottish National Party's claims, including that Scotland will keep the British pound as its currency and automatically join the European Union, have been challenged.

“Support for the union -- so the ‘no’ to independence -- is double the support that there is for independence,” Tom Mludzinski of Ipsos MORI told CTV News.

“Of course now with the decision we are taking in Scotland next year, we're interested in what happened in detail in Quebec and in Canada both 20 years ago and a generation ago,” Michael Moore, Britain’s Secretary of State for Scotland told reporters after Chretien spoke.

A survey conducted in January showed support for sovereignty at 23 per cent -- an all-time low in Scotland.

Warning against over-confidence in the face of any leads, Chretien reminded the London crowd that the “no” side was well ahead for most of the 1995 Quebec referendum campaign but only won by a sliver of a margin – less than 1 per cent.

“I said take it seriously and you never know. Two weeks before the referendum, we had no doubts and suddenly that turned,” Chretien told reporters after his speech.

Earlier this year, Quebec Premier Pauline Marois held a low-key meeting with her Scottish sovereigntist counterpart Scottish National Party leader Alex Salmond.

The meeting was kept largely out of the media spotlight, but Marois reportedly offered the Scottish government extensive data collected by the PQ from both Quebec referendums.

With a report by CTV News’ Ben O'Hara-Byrne