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By Ben Hirschler and Martinne Geller
LONDON, June 24 (Reuters) - Shocked chief executives fromMumbai to Denver woke up on Friday to face tough decisions overhow to respond to Britain's vote to leave the European Union.
In Britain itself, businesses as diverse as engineeringgroup Rolls-Royce, drugs giant AstraZeneca, housebuilders and makers of Scotch whisky were braced fordisruption in the short and long term as the pound plunged toits lowest level since 1985.
Big business -- with a very few exceptions -- has beenstrongly in favour of remaining in the world's biggest tradingbloc, primarily because of ease of access to 500 millionEuropean consumers.
"The weeks and months ahead are going to be a nervy time forbusiness leaders," Simon Walker, director general of Britishbusiness lobby the Institute of Directors, said on Friday.
Jaguar Land Rover, Britain's biggest carmaker, has estimatedits annual profit could shrink by 1 billion pounds ($1.4billion) by 2020 if Britain returns to World Trade Organizationrules for trade with Europe.
Shares in the company's owner, India's Tata Motors, slumped more than 10 percent.
Makers of Scotch whisky, who export about 90 percent of whatthey produce, have stressed the importance of the EU, whichswallows about a third of those exports, but also the clout EUmembership gives in negotiations with fast-growing markets suchas India, which has a 150 percent tariff on imported spirits.
Some investors warned of a coming British or even globalrecession as sterling collapsed to hit its lowest since 1985,while FTSE futures fell 8 percent.
The president of Japan's Nippon Steel & Sumitomo Metal, the world's second-largest steelmaker, said the votewas extremely disappointing. "We are greatly concerned for thenegative impact this will have, not only on Britain and the EUbut also on the global economy," said Kosei Shindo.
Martin Sorrell, the boss of the world's biggest advertisinggroup WPP, said: "This decision will create tremendousuncertainty, which will slow economic activity and decisionmaking."
STERLING HEADACHE
Big swings in sterling will be a headache for someinternational companies, with a fall in the currency hittingprofits earned in Britain.
International companies with sizeable sterling exposureinclude Denver-based Molson Coors, owner of Carlingbeer, which is heavily reliant on the UK.
Aside from market access, streamlining of regulations withinthe EU has made life simpler.
Pharmaceutical companies, for example, enjoy a one-stop shopin the form of the European Medicines Agency -- based in London- which approves new drugs for all EU countries, while the EU'sopen airspace deals have fostered a surge in air travel andcommon policies on agriculture and food safety have allowed forsmoother supply chains and richer eating.
Companies in those sectors have fretted that Britain outsidethe bloc would disrupt the regulatory landscape.
"This creates immediate challenges for future investment,research and jobs in our industry in the UK," said MikeThompson, CEO of the Association of the British PharmaceuticalIndustry.
AstraZeneca said it was concerned for the competitiveness ofthe British life sciences industry and would work to ensurepatient access to medicines, amid worries that leaving the EUcould delay drug approvals.
Access to workers is another important factor for companies.Automotive industry executives, who are heavily reliant onexports, ranked tapping a skilled workforce a close second toaccessing EU markets in a survey on reasons to remain in March.
Ahead of the vote, some British-based multinationals such asDiageo, Unilever and Rolls-Royce had expressedtheir support for "Remain" directly to employees, although moststopped short of this.
Government figures show 12.6 percent of Britain's economicoutput is linked to exports to the EU's 27 other members, forwhom only 3.1 percent of output is linked to exports to Britain.And 80 percent of British businesses trading overseas do so withthe EU.
The Confederation of British Industry has estimated therecould be between 550,000 and 950,000 fewer jobs by 2020 in theevent of Brexit.
For banks, a huge concern has been the threat that financialinstitutions based in London could lose their EU "passports", orthe automatic right to sell services across the bloc undersingle low-cost system. That has made bank shares particularlyvolatile in the run-up to the referendum.
Brexit uncertainty has also helped push British merger andacquisition activity this year at its lowest as a proportion ofglobal activity since records began in 1980. ($1 = 0.7428 pounds) (Additional reporting by Kate Holton, Ritsuko Ando and YukaObayashi; Editing by Keith Weir)
