The idea of splitting up RBS into a "good bank" and "bad bank" is outdated, unhelpful and a distraction, the CBI boss has told ITV News.
The CBI conference opened with a friendly warning to the Prime Minister on the dangers of isolating the UK in Europe.
The Scottish CBI is "not convinced of the business and economic case" for independence, it will announce today.
Business leaders have said political uncertainty about the outcome of the next General Election remains a "major risk to the recovery".
The Confederation of British Industry (CBI) urged politicians to push ahead with boosting the supply of homes and taking decisions on major infrastructure projects.
The major parties need to show they would "stick with what is working" after next year's election, the CBI's chief policy director Katja Hall said, urging them against costly "political positioning".
She added: "(Positioning) must not be allowed to stifle investment, whether it's an unrealistic immigration target, unjustified interventions into specific markets, flirting with leaving the European Union, delaying vital long-term infrastructure projects or restricting labour market flexibility."
Business leaders have predicted interest rates will need to rise early next year as they issued a warning about "unsustainable" house prices.
The Confederation of British Industry (CBI) expects a rise of 0.25 per cent in the first three months of 2015, from 0.5% to 0.75%.
The business lobby group previously predicted the Bank of England would have to start raising rates in the third quarter of next year - but has now brought that forward to the first quarter.
The CBI also raised its forecast for the UK's gross domestic product forecast for this year from 2.6% to 3%.
Director-general John Cridland said property values were expected to rise by 8.2% this year, and 5.1% next.
But he warned: "We have to remain alert to the risks posed by unsustainable house price inflation, and the (Bank's) Financial Policy Committee is poised to act when necessary."
The CBI said:
Our conclusion is that the White Paper does not offer a coherent vision for how or why an independent Scotland would be better off from erecting barriers between itself and its biggest export market.
The loss of many of the strengths of the union would open the nation to a higher risk from economic shocks.
Independence would be a major economic upheaval with uncertain consequences.
For this reason, we believe that the best way to deliver jobs and prosperity for the people of Scotland is for Scotland to remain a part of the UK.
In short, Scotland and the UK are stronger together.
The Scottish Government blueprint for independence "does not add up", with Nationalists ignoring the need for deficit reduction while promising at least £670 million of "unfunded" spending commitments, a business leader claimed.
John Cridland, director-general of the CBI, said the "lack of clarity" in the White Paper could put an independent Scotland's future success in jeopardy.
He hit out as the business organisation - which represents 240,000 firms across the UK - published its response to the independence White Paper launched by First Minister Alex Salmond last November.
The business community's reaction to today's Budget was broadly positive, with the Confederation of British Industry (CBI) and the British Chambers of Commerce offering strong endorsements.
Business wanted disciplined Budget that was geared towards jobs+wealth creation - that’s what Chancellor delivered http://t.co/HUSlhct5o6
The head of the CBI, John Cridland, said: “This was a make or break budget coming at a critical time in the recovery and the Chancellor has focused his firepower on areas that have the potential to lock in growth.”
The Federation of Small Businesses also hailed the Government's business-friendly approach.
Welcome focus on manufacturing; increased investment allowance, cuts to energy bills - will create jobs & strengthen this sector #Budget2014
Business group the CBI has said the UK is starting to see "the right kind of growth" as it lifted it predictions for expansion in the economy this year from 2.4% to 2.6%.
It said business investment would make a positive contribution this year, rising at the fastest rates since 2007, while increasing exports would help net trade play a small role in supporting the recovery.
The upgraded forecast for 2014 reflects a stronger than expected performance at the end of last year. However, the CBI has downgraded growth expectations for next year from 2.6% to 2.5%.
The CBI expects that unemployment reached the Bank of England's 7% "forward guidance" threshold in the final quarter of last year - for which labour market figures have not yet been published.
The guidance pledges that policy makers will not begin to consider a rise in interest rates until the threshold has been reached.
But the CBI predicts that despite having fallen to this level, continued low inflation and spare capacity in the economy mean that interest rates will not go up until the third quarter of 2015.
David Cameron says he aims to get "every penny for value for money" from the investment in the controversial HS2 rail project.
Speaking at the annual CBI conference, Mr Cameron insisted the scheme would "unite the country and drive economic growth".
The Prime Minister said the leader of the HS2 scheme, Sir David Higgins, would "drive every extra bit of cost out of the project" so it comes in under the estimated £50 billion budget that has been set.
The Prime Minister went on to claim that critics of the project were "putting the country's future at risk" and called for a "concerted consensus" across business and politics to get behind the project.
Boris Johnson has expressed frustration at the drawing out of the HS2 project timescale.
The Mayor of London wrote in The Telegraph that China built its own high-speed rail in just two years.
Meanwhile, he said, Labour are delaying the project further by "shamelessly courting the sceptic vote".
Nigel Farage has hit out at a report published by the Confederation of British Industry that says the UK is "overwhelmingly" better off in the European Union.
The UKIP leader said: "There is this deeply flawed view that leaving the EU would somehow mean a sudden end to trading with Europe.
"The CBI does not consider the more realistic option that if we left the single market and freed ourselves from its red tape and politicised agenda we would still be able to continue to trade strongly with Europe on our own terms.
"Instead the CBI are proponents of this skewed view that Britain can renegotiate terms with the EU to create a more streamlined relationship.
"That would have to involve treaty change but the European Commission President Jose Manuel Barroso has ruled that out.
"Without treaty change there can be no significant renegotiation at all."
A Labour government would set up an independent infrastructure commission to end delays in major infrastructure projects such as HS2, according to Ed Balls.
The shadow chancellor is expected to tell today's Confederation of British Industry conference that an infrastructure commission would "end dither and delay in infrastructure planning and build the consensus on infrastructure that we need to invest for the long-term".