STANDARD LIFE chief executive David Nish has insisted that the Edinburgh-based pensions and investment house acted responsibly when it revealed earlier this year it had contingency plans to relocate operations to England.

The 189-year-old institution's comments were seen as an intervention in the independence referendum debate on the side of the "no" campaign.

Mr Nish said: "The reaction is that we acted responsibly in terms of how we both assessed the situation and how we ended up communicating it.

"I think there is a strong level of understanding from our customers about our responsibility to them and we that we will take the action necessary to protect them."

He added: "We have not seen significant outflows from our business, if there was a concern about that."

In its annual report published in February, Standard Life chairman Gerry Grimstone, said Scotland has been a great base for the company but "if anything were to threaten this, we will take whatever action we consider necessary - including transferring parts of our operations from Scotland".

Standard Life's intervention was followed by a similar warning by Keith Cochrane, chief ­executive of engineering giant Weir Group, who said "the costs of independence are guaranteed but the benefits are uncertain". He said his company would consider moving its headquarters from Glasgow.

Dundee-based investment company Alliance Trust, for its part, has set up companies south of the Border to allow it to relocate some businesses.