Royal Bank of Scotland has confirmed plans to move to England if Scotland votes for independence next week. RBS said it believed it would be necessary to re-domicile the bank's holding company and its primary operating unit RBS Plc as part of contingency planning in the event of a 'yes' vote on September 18.The group, based in Scotland since 1727, said there were "a number of material uncertainties" arising from the referendum which could affect its credit ratings "and the fiscal, monetary, legal and regulatory landscape to which it is subject."It said such a move should not affect everyday banking services throughout the British Isles and would mitigate risks and provide clarity to staff, customers and shareholders.RBS added that it planned to keep "a significant level of its operations and employment in Scotland to support its customers there and the activities of the whole bank."Rival Lloyds Banking Group and insurer Standard Life have also threatened to quit Scotland if Scots vote for a split.London financial newspaper City AM reported on Thursday that Lloyds' contingency plans included "the establishment of new legal entities in England", although the bank added that there would be no immediate changes or issues which could affect its business or customers.A poll published on Wednesday night by pollster Survation and Scotland's Daily Record newspaper showed the 'no' campaign with a lead of 53% to 47% over the separatists.It is likely to boost the unionist campaign following a poll at the weekend showing the 'yes' campaign with a lead, although Scottish First Minister Alex Salmond has dismissed last-minute visits to Scotland by the leaders of the main Westminster political parties as a panic move.