They also foresaw Indian companies having to shift their operations out of the UK to other European locations.
While the government and RBI sought to calm the nerves saying any impact on India would be transient lasting just for a few days, the exporters warned of immediate impact on their margins due to volatility in rupee value.
Tata group saw shares of their various companies including Tata Motors and Tata Steel with significant exposure to UK taking a big hit.
Exporters feared that the turmoil in global currencies would bring in more currency risks and could prove disastrous for the world trade, although rupee depreciation may appear to be good in longer term for those shipping goods overseas.
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Mazumdar-Shaw said India cannot be in a denial mode that it will be immune to Brexit, adding that there is likely to be mayhem for several weeks before things stabilise.
Tech investor and former Infosys director T V Mohandas Pai said Indian IT players catering to clients in the financial services space in London may shift their operations to other parts of Europe as a cheaper Pound Sterling will have the biggest impact on these firms.
Europe is the second largest market for Indian IT-BPM industry, constituting almost 30 per cent of the sector's export revenue of about USD 100 billion. The UK plays a key role within this market. In addition to representing a large share of Nasscom's members' activity in Europe, many use Britain as a gateway for further investment across the EU.
Concerns further mounted as commentators said that Britain's exit could mean that the EU could slip into recession while Indian firms would also need to rework their strategy to use UK as a gateway for their European operations.
Financial services major Ambit Investment Advisors' CEO Andrew Holland said Brexit is a huge negative outcome and has far reaching ramifications for global markets and economies.
Andrew, who hails from Britain and has been active in the Indian equities markets since 2006, there will be speculation over whether Scotland will call for a new referendum given they voted to "remain" in the European Union.
"Elsewhere in Europe, other countries may well follow suit and hold their own referendums and concerns would rise as to whether the European Union will disintegrate," said Holland who has previously been with Merrill Lynch as MD and Head of Proprietary Trading.
"We could therefore re-visit the concerns of earlier this year that the global economy could now take a shift down and central banks have fired most of their ammunition and anyways it is not really working. So politics will be at the forefront of markets and with that huge volatility," he added.
Stating that markets are going "haywire" after going into a complacent mode into the lead up to referendum, he said going ahead "volatility will remain abound as positions get un-wound and markets speculate on the future of Europe.
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Industry body Assocham Secretary General D S Rawat said: "Since India has a huge corporate investment in the UK economy, Indian firms with manufacturing or other facilities in Britain will have to realign their business plans."
Apparel Export Promotion Council (AEPC) Chairman Ashok G Rajani said: "Britain is our largest market in the European union accounting for around 30 per cent of our exports to EU. It's exit would significantly dilute the relevance of EU FTA for us.
CII President Naushad Forbes said with the UK voting to leave the EU, Indian companies will re-engineer their European strategy.
"This should not be an issue. India will not be affected due to Brexit if we look at a mid to long term perspective," he said.
Commenting on the development, the over USD 100 billion Tata Group said access to markets and skilled workforce will remain important considerations after Britain's decision to leave EU.
"Each company continuously reviews its strategy and operations in the light of developments, and will continue to do so. Access to markets and to a skilled workforce will remain important considerations," a Tata Sons spokesperson said in a statement.
Tata Motors-owned Jaguar Land Rover said it is "business as usual" and will manage the long-term impact and implications of Brexit, insisting "nothing will change" overnight for it and the automotive industry.
Another homegrown multinational Mahindra group also said Brexit will result in uncertainty in the immediate aftermath which will moderate over time.