Scotland's First Minister Alex Salmond has accused Westminster of having "no contingency plans" for a 'Yes' vote in Scotland.
He accused pro-Union politicians, including the Chancellor George Osborne, of contributing to a "lack of confidence in the UK government" on the part of the financial markets.
George Osborne warned Scotland that if it votes Yes to independence there would be no currency union.
The Chancellor told BBC's Andrew Marr show that sharing currency after independence would be equivalent to a couple divorcing but sharing the same bank account.
No ifs, no buts. We will not share the pound if Scotland separates from the rest of the UK.
However, Mr Osborne did promise to announce plans for "more tax powers, more spending powers, more plans for powers over the welfare state" in the next few days.
He said it was "clear" Scotland wanted more autonomy and the Conservatives, Liberal Democrats and Labour had agreed to "deliver" on that.
Chancellor George Osborne said plans to devolve more powers to Scotland inside the UK will be unveiled in the next few days after a shock poll put the Yes campaign in the lead for the first time.
Final touches are being put to proposals for "much greater" fiscal autonomy and tax-raising abilities, Mr Osborne told the BBC's Andrew Marr show.
He also said the YouGov research for the Sunday Times - which found pro-independence campaign ahead by 51% to 49% - should galvanise those who wanted to keep the union together.
This country faces a very, very big choice. Scotland faces a very big choice. If people were in any doubt that they can stay at home, that they don't need to go out to the polls and vote No to avoid separation, they won't be in that doubt today.
They should also be in no doubt about the consequences of this decision - one of which is that Scotland will not be sharing the pound as an independent country with the rest of the UK if the separatists win the vote.
George Osborne's pet cat Freya has been hit by a car.
But a Downing Street spokeswoman stressed the wandering feline, who went missing earlier this year, was not seriously injured.
It is unclear where the accident happened or whose car was involved.
The news came as cat enthusiasts around the globe celebrated World Cat Day.
In May, the Chancellor's cat was chauffeur-driven back home after turning up frightened and lost in Vauxhall where she was found by homelessness outreach worker Kate Jones who identified her from the tag on her collar.
Ms Jones later posted a picture of the cat with a note to remind Mr Osborne that while she had been given shelter for the night in this instance, most homeless people are not so fortunate.
Steven Swinford, senior political correspondent at The Daily Telegraph, has tweeted:
George Osborne says Baroness Warsi's decision to resign over Gaza is 'disappointing and frankly unnecessary'.
Chancellor George Osborne will today set out the government’s vision for a northern economic powerhouse.
He will be in Manchester to hear proposals for a £15 billion plan to improve the future of the northern economy in Leeds, Liverpool, Manchester, Newcastle and Sheffield over the next 15 years.
Mr Osborne is expected to say: "Today I give you this personal commitment. Work with me over the coming months and together we will make a reality of the plan I've set out for the Northern Powerhouse.
“I'm ready to commit new money, new infrastructure, new transport and new science. And real new civic power too."
The Chancellor has urged Israel and Hamas to deliver a "permanent ceasefire" as a 72-hour truce between the sides collapsed.
George Osborne said, "What we want to see - and what the whole world wants to see - is an immediate ceasefire, a ceasefire that holds".
Chancellor George Osborne has said that "free and impartial advice" on pensions will be delivered by the Government using organisations like Citizen's Advice Bureau and Age UK.
Mr Osborne said the steps meant people could "make the right choices" and know that they are getting "good, independent guidance that is right for them".
Planning for retirement is a crucial life stage, and it is important that people feel well-informed and confident in the decisions they make, the chief executive of the Money Advice Service (MAS) said. Caroline Rookes added:
The Money Advice Service welcomes the Treasury's announcement that we will have a role in the provision of the retirement guidance guarantee.
We are pleased to have this opportunity to build on our existing work helping people as they approach retirement and with wider money issues.
Millions of people will get free, impartial advice on how to make the most of their retirement savings under George Osborne's radical shake-up of the pension system. Pensions expert Ros Altmann, the Government's older workers' business champion, said:
The decision that guidance must be impartial and separate from the industry is a real game-changer and will help equip people to make the right decisions for them.
The challenge is now firmly with the industry to develop the products that people need, rather than simply the products they wish to sell.