A member of Britain's diplomatic service has won a 100,000 euro ($140,000) cash prize for his proposal outlining a blueprint for Britain after its potential exit from the European Union.

Iain Mansfield was awarded the "Brexit Prize" at an event hosted by the Institute of Economic Affairs (IEA) in central London on Tuesday night. Mansfield, 30, is the Director of Trade and Investment at the UK's embassy in the Philippines. His winning proposal, "A Blueprint for Britain: Openness not Isolation" calls for the UK to join Iceland, Liechtenstein, Norway and Switzerland in the European Free Trade Association (EFTA) and introduce a "Great Repeal Bill" to review and ultimately dismantle EU regulations.

Mansfield argues that such actions would promote trade between Britain and emerging markets while reducing bureaucratic burdens on British business. He claims that UK GDP would increase by £1.3 billion ($2.17 billion) under his proposal.

The IEA, a nonpartisan free-market think tank based in London, introduced the Brexit Prize in July 2013 to "improve the debate about what an independent Britain would and could look like outside the EU, given that exit is an increasing possibility after the next election."