British Prime Minister Theresa May and European Commission President Jean-Claude Juncker walk together during a break in the European Union leaders summit in Valletta, Malta, February 3, 2017. REUTERS/Yves Herman
Sat Feb 4, 2017 | 1:19am GMT
The British Influence think-tank had argued that although last June's referendum had resulted in a "leave" vote, it had not been a mandate for the government of Prime Minister Theresa May to take Britain out of the single market.
But the High Court rejected that argument, with judges saying they would give their reasons later.
Membership of the EEA, which includes the EU countries as well as Norway, Iceland and Liechtenstein, provides preferential access to the single market.
Campaigners for a so-called soft Brexit say continued unfettered access to the single market will be vital for Britain's economic prospects once it leaves the EU.
But May said in a speech last month that Britain would leave the single market, although she promised to seek the greatest possible access to European markets.
A government spokesman welcomed Friday's judgement.
"We are glad this attempt ... has been dismissed," he said in a statement.
"As the prime minister has said, we will not be a member of the single market and we will be seeking a broad new partnership with the EU including a bold and ambitious free trade agreement."
The British Influence action was separate from another legal challenge last year that ultimately went against the government and forced it to seek parliamentary approval for triggering the two-year divorce process from the EU.
May has said she plans to start the formal divorce by the end of March.
http://uk.reuters.com/article/uk-britain-eu-eea-challenge-idUKKBN15I1Z0