Britain's membership of the European Union (EU) would be best for the success of its car industry, an industry report said on Wednesday. "The attractiveness of the UK as a place to invest, and the competitiveness of the domestic automotive industry, is enhanced by the UK's membership of the EU," said the report released by the Society of Motor Manufacturers and Traders (SMMT). Access to the single market, integrated European supply chains, EU innovation funding, free movement of labour and the ability to influence harmonised technical regulations and product standards are key EU benefits, said the report entitled The UK Automotive Industry and the EU. "The position of the UK automotive industry is clear - being part of a strong Europe is critical for future success," said Mike Hawes, SMMT Chief Executive. The British automotive manufacturing industry accounted for around 3 percent of the country's GDP with a turnover of nearly 100 billion U.S. dollars in 2012. The SMMT study, done by accountancy firm KPMG, came as the anti-EU UK Independence Party (UKIP) has gained popularity and many Britons demanded withdrawal from the EU. Prime Minister David Cameron said he will stage an in-or-out referendum on EU membership by the end of 2017 if he wins next year's general election.