Senior Scottish financiers have rejected warnings that the country's banking sector could be seriously damaged by independence, insisting that a currency union was the most likely result of a yes vote.
The joint letter to the FT by seven business leaders, including Sir Donald MacKay, the former chairman of the Scottish Mortgage Investment Trust, came as Standard Life again said it had serious concerns about Scotland's currency, its EU membership and taxation after a yes vote.
The Edinburgh-based pensions firm said six months ago that it might shift large amounts of its business to England after a yes vote, and as it unveiled a rise in profits on Tuesday, it said it was continuing to plan a possible move south.
Standard Life said further clarity had not been provided on a number of issues affecting its four million customers, which included the shape of the monetary system, financial services regulation and individual taxation around savings and pensions.
The business leaders, all known to support or be sympathetic to independence, said the greatest threat to Scotland's significant financial services sector came from the risks of a UK-wide referendum on EU membership – a view endorsed by a recent surveys of chief executives, they said.
After attacking the neutrality of a new inquiry into independence by the Labour-dominated Scottish affairs select committee at Westminster, the signatories, who include Jim Spowart, a founder of the Standard Life bank, and the former RBS chairman Sir George Mathewson, said: "There is a positive outlook for the sector because we believe the likelihood of a currency union is strong. It is not only in the best interests of Scotland and the rest of the UK, but of our industry.
"The financial sector in Scotland will always prosper because we have the skills, the talent and the connections that are needed to thrive," they concluded.
As referendum campaigners prepare for the first televised debate between Scotland's first minister, Alex Salmond, and the leader of the no campaign, Alistair Darling, the pro-independence Yes Scotland disclosed that Ralph Topping, the outgoing chief executive of the bookmakers William Hill, had endorsed a yes vote.
Topping, who returned William Hill to the FTSE 100, said he believed there would be a currency union, despite pledges from the chancellor, George Osborne, the chief secretary to the Treasury, Danny Alexander, and the shadow chancellor, Ed Balls, that a sterling pact would be vetoed.
"It is not the location of a bank's brass plate in Scotland, but rather the concentration of economic assets in the rest of the UK that matters to British financial stability," Topping said.
"The Treasury should stop playing politics and listen to market voices wanting a collaborative approach to the monetary system between an independent Scotland and the rest of the UK. In this respect, common sense economics was always going to trump politics."
A pillar of the Scottish finance industry, Standard Life caused alarm when it said in February it would take whatever action necessary to protect its business, including moving large chunks of its operations to England, despite its 189-year Scottish heritage. It has been registering companies in England as part of contingency plans.
Its chief executive, David Nish, said the company, which employs about 5,000 people in Scotland, had received "a very strong measure of support" from shareholders for its plans. He denied suggestions that large numbers of angry customers had closed accounts with the firm. "We are unaware of any significant amount of money being withdrawn with regards to this," he said.
Severin Carrel and Julia Kollewe