Economic organisations that warned a vote to leave the European Union would damage the British economy have already been proved "wildly wrong" in a series of predictions, according to an analysis by a leading pro-Brexit campaign.

Leave Means Leave highlighted a series of forecasts by bodies including the International Monetary Fund (IMF), World Bank and the Organisation for Economic Co-operation and Development (OECD) which it described as "far off the mark".

The analysis came as Lord Young of Graffham, who was Trade Secretary under Margaret Thatcher greeted news of a boost in Britain's productivity as proof that predictions of a "car-crash" or "fourteen years of doom and gloom" were wrong.

Figures from the Office for National Statistics showed labour productivity expanded by 0.9 per cent in the third quarter of last year - the largest rise since 2011. Lord Young said the figures showed people should "have faith in entrepreneurial Britain".