Lloyds Banking Group is not currently preparing to move operations out of Scotland in the event of a Yes vote, but says there could be "material costs" from constitutional change.

The bank meanwhile faces a potentially embarrassing threat of industrial action from part of its workforce after pushing through a cap on its final salary pension scheme benefits at yesterday's annual meeting.

Chairman Lord Blackwell, responding to a shareholder question at a well-attended meeting in Edinburgh, said the referendum created uncertainties which translated into risks around compliance, the tax regime, and funding structures, adding; "We are not at this point planning any move, because we don't know what the result will be...if there were changes we would seek to work with all the relevant authorities to ensure we had a way forward to achieve our core purpose of serving our customers across the UK."

Chief financial officer George Culmer told another shareholder: "There could be material costs under certain eventualities."

Shareholders were told that Lloyds had returned to profit last year and its share price had risen 78 per cent since June 2011, showing that management had earned its rewards.

The bank, still 25 per cent owned by the taxpayer, was proposing changes to executive pay designed to ensure bonuses could be up to double fixed salary rather than only 100 per cent of salary. Lord Blackwell said: "We continue to believe it's desirable for a significant part of executive remuneration to be earned as variable pay ... we propose to use the discretion allowed under the legislation."

He said variable pay that could no longer be delivered as cash would convert into shares to invest over five years.

There was however a 12.7 per cent vote against the remuneration implementation report, though the remuneration policy report received 98 per cent support and the adoption of new variable pay for senior staff almost 99 per cent support.

Lord Blackwell said: "The board is very conscious of shareholder desire that improving performance is reflected in the resumption of dividends.

"The low risk inherent in our largely UK focus is now being recognised by the regulator as are the changes to capital, liquidity and funding position." Discussions with the Prudential Regulation Authority over resuming the dividend "at a modest level" would begin later this year, Lord Blackwell said.

But the bank's efforts to preserve the status quo for senior executives were cited by trade unions represented at the meeting who were protesting at the cap on final salary scheme benefits.

The Unite union said its survey had found 74 per cent of staff "prepared to leave the bank" and 94 per cent prepared to take some form of industrial action in protest at the changes.

An Accord union representative said a ballot of 27,000 former HBoS staff had found 85 per cent saying they had lost trust and confidence in management and 80 per cent said they would be prepared to join industrial action.

A third union, LTU the largest in the group, handed out leaflets outside the meeting claiming that some managers stood to lose six-figure sums from their pension values.

Antonio Horta-Osorio, chief ­executive, said: "We have over the past three years systematically increased overall remuneration above inflation. The pension cap applies to one-third of staff."

Lord Blackwell commented that the lost bonuses complained of by Accord were due to the group's scrapping of sales-linked incentives as part of its move to being an "ethical bank".