Ministers are facing a legal challenge over whether leaving the EU means automatic withdrawal from the single market.
Pro-EU think-tank British Influence is writing to Brexit Secretary David Davis to seek clarification on the Government’s position regarding the UK’s status in the wider European Economic Area (EEA) when it quits the EU.
The think-tank has said a legal challenge is likely as it believes leaving the EU does not mean quitting the EEA which extends the single market’s tariff-free trade in goods to countries like Norway, Iceland and Liechtenstein.
A legal challenge could result in Parliament being given the final say on EEA membership.
A spokesman for British Influence told the Press Association: “It is likely there will be a legal action because, in our view, the Government has taken a stance that leaving the EU means leaving the single market.”
Chairman of the Regulatory Policy Institute and emeritus professor at Hertford College, Oxford, Professor George Yarrow, told the BBC: “There is no provision in the EEA Agreement for UK membership to lapse if the UK withdraws from the EU.
“The only exit mechanism specified is Article 127, which would need to be triggered.”
Jolyon Maugham QC, of Devereux Chambers, told the BBC: “My own view is that you do not automatically leave the EEA. Given Article 127 provides an express mechanism for withdrawal, it implicitly excludes other implied mechanisms for withdrawal such as ceasing to be a member of the EU.”
A Government spokesman said the UK would automatically stop being a member of the EEA once it leaves the EU.
“As the UK is party to the EEA Agreement only in its capacity as an EU member state, once we leave the European Union we will automatically cease to be a member of the EEA.
“The future relationship between the UK and the EU will be subject to negotiations. It’s not in the UK’s interest to give a running commentary on our thinking that could undermine our negotiating position.
“The referendum result will be respected and we intend to invoke Article 50 no later than the end of March next year.”