More than 130 business leaders recently signed a letter calling for the UK to stay together, while about 200 business leaders are standing firm on the other side of the debate.(http://bit.ly/1sYUlXD)

Following are comments of Britain's top companies and firms with operations in the UK on the Scottish referendum:

Sept. 11

Royal Bank of Scotland Group Plc (>> Royal Bank of Scotland Group plc) warns it "would be necessary to re-domicile the bank's holding company", if Scots vote for separation.

Ad firm M&C Saatchi Plc (>> M&C Saatchi Plc) says keeping track of the referendum as its largest UK client - the Royal Bank of Scotland - may relocate to England if the UK is split.

TSB Banking Group Plc (>> TSB Banking Group PLC), which is part-owned by Lloyds, says may relocate some operations to England should Scotland vote for independence.

National Australia Bank Ltd (>> National Australia Bank Ltd.) says contingency plans for its Scotland-based subsidiary, Clydesdale Bank, include moving to England if Scotland votes to end its union.

Sept. 10

Part-nationalised British bank Lloyds Banking Group Plc (>> Lloyds Banking Group PLC) says contingency plan includes setting up "legal entities in England", if Scotland votes for independence.

BP Plc (>> BP plc) Chief Executive Bob Dudley says he hopes Scots vote against independence because the United Kingdom would better provide the stability required for long-term investment in the oil-producing North Sea.

Edinburgh-based insurer Standard Life Plc (>> Standard Life Plc) says the referendum would have no impact on dividend payments or its London listing and reiterates it could transfer business to England if necessary.

The head of one of Britain's largest defence suppliers, France's Thales SA (>> THALES), voices concerns over jobs and investment if Scotland votes to leave.

Sept. 3

If Scots vote to break up the UK, it would cost everybody money, says Tom McPhail, head of pensions research at fund supermarket and financial advisor Hargreaves Lansdown Plc (>> Hargreaves Lansdown PLC).

Aug. 29

Exova Group Plc (>> Exova Group Plc) CEO cautions that a vote in favour of a split would result in some short-term uncertainty for its regional business. The material testing services provider says could easily shift its small head-office out of Edinburgh, if needed.

Aug. 21

Uncertainty over Scotland's currency arrangements could prompt capital flight, leaving its financial system in a "parlous state", writes Douglas Flint, chairman of HSBC Holdings Plc (>> HSBC Holdings plc).

Aug. 19

Edinburgh-based John Menzies Plc (>> John Menzies plc) says to wait for the outcome of the vote to decide whether to make any changes.

Aug. 12

UK insurer Prudential Plc (>> Prudential plc) says to continue operating in Scotland and fulfilling its obligations irrespective of the outcome of the vote.

June 25

Royal Bank of Scotland Group Plc (>> Royal Bank of Scotland Group plc) says considering its options as a 'yes' vote would have implications for its credit rating, taxes and regulation.

June 2

BAE Systems Plc (>> BAE Systems plc) chief executive says a split could complicate the issue of pension schemes and would force Europe's biggest defence contractor to talk to its major UK customers.

May 31

Kingfisher Plc's (>> Kingfisher plc) chief executive says the home improvement retailer's DIY chain, B&Q, would not leave the region in case of a vote for independence.

May 16

Oil services company Amec Plc (>> AMEC plc) says hasn't made any specific treasury planning and will wait for the outcome of the referendum.

March 6

Aggreko Plc (>> Aggreko plc), the world's biggest temporary power provider, warns it would have to split its UK business in half, leading to significant costs, if Scots vote for independence.

Royal Dutch Shell Plc , a key player in the North Sea oil and gas fields off Scotland, cautions that a vote for independence could mean greater uncertainty for the energy industry.

Feb. 28

International Consolidated Airlines Group SA (>> International Consolidated Airlines Grp) chief executive says Scottish independence would be "slightly positive" as an independent Scotland could move to eventually abolish air passenger duty. IAG owns British Airways.

Ryanair Holdings Plc's (>> Ryanair Holdings plc) CEO supports Scottish government's intentions to abolish air passenger duty if the United Kingdom was split. (http://bbc.in/1qy7SFZ)

Feb. 4

BP Plc (>> BP plc) chief executive warns that Scottish independence could cause his company "uncertainties".

(Compiled by Esha Vaish in Bangalore; Editing by Sriraj Kalluvila)