Clashes between Yes and No campaigners in Scotland's independence fight forced U.K. Labour Party Leader Ed Miliband to cancel a walkabout in Edinburgh Tuesday intended as an eleventh-hour push to sway voters to remain part of Britain.

Scotland's Daily Record newspaper reported that Miliband was mobbed by campaigners from opposing sides as he visited the St. James shopping centre in the capital.

Britain Scotland

U.K. Labour Leader Ed Miliband abandoned a voter meet and greet at an Edinburgh shopping centre Tuesday after clashes between opposing sides became too chaotic. He was there campaigning for the No side. (David Cheskin/Associated Press)

Shouts of "Vote Yes," "Vote No" and "You're a liar" were heard coming from the crowd, and some onlookers were pushed and trampled as activists jostled to get past media and shoppers to get closer to the politician, the paper reported.

Miliband's team had not publicized the location of his visit precisely to avoid such a scene and to allow him to speak directly with voters and attempt to convince those still on the fence to vote No in Thursday's referendum.

British and Scottish media reported that Miliband only got a chance to speak to the public for a few minutes before the noise and crush of people forced him to abandon the effort.

Debate gets uglier

The two sides in Scotland's independence debate scrambled Tuesday to convert undecided voters, with just two days to go until a referendum on separation.

The pitch of the debate has grown increasingly urgent. Anti-independence campaigners argue that separation could send the economy into a tailspin, while the Yes side accuses its foes of scaremongering.

After a late poll surge for the pro-independence side, the No campaign is striving to persuade Scots that they will gain more autonomy if they do not secede.

Miliband was one of three U.K. party leaders to sign a pledge published in the Daily Record Tuesday promising Scots "extensive new powers" — including tax-raising authority — if they remain part of the United Kingdom. Miliband signed the pledge along with Prime Minister David Cameron and Liberal Democrat chief Nick Clegg.

Labour Party politician Douglas Alexander said a No vote meant "faster, safer, better change for Scotland," while independence would bring "risks, uncertainties and costs."

"With just 48 hours to go, they can't even tell us what currency we'll be using," Alexander told No supporters in Edinburgh's financial district.

'Desperate offer of nothing'

The pro-independence Scottish government says Scotland will continue to use the pound sterling, but the British government insists it won't agree to a currency union.

David Cameron

Britain's Prime Minister David Cameron has said he'll be heartbroken if Scotland leaves the U.K. (Andrew Milligan/PA/The Associated Press)

The Yes campaign says the promises of new powers are vague and reveal the No side's desperation.

"This last-minute desperate offer of nothing is not going to dissuade people in Scotland from the huge opportunity of taking Scotland's future into Scotland's hands this coming Thursday," First Minister Alex Salmond told the BBC.

Polls suggest the outcome will be close, and several hundred thousand voters who have yet to make up their minds could determine whether Scotland leaves its 307-year-old union with England.

For some voters, concerns about economic insecurity and job losses are a powerful reason to reject independence.

Property developer Alex Watts said international investors were putting Scottish projects and purchases on hold because of the uncertainty around the vote.

"What the property industry needs in Scotland is more certainty and stability," he said. "Why should we take the risk? Scotland is not the only place to invest in."

Others, though, say the negative campaign of politicians on the No side has driven them into the Yes camp.

"Rather than putting their own case for why we should stay together they're trying to scare us into not separating," said Mike Smith, who sells leather goods from a stall along Edinburgh's Royal Mile.

"If that's what they're doing now, what are they doing the rest of the time?"

With files from CBC News