Johnson, who has served as Shadow Chancellor of the Exchequer and a number of other cabinet positions under Tony Blair and Gordon Brown, highlighted why this referendum is different to that of 1975 for the Labour Party. This time, Labour peers have unanimously supported the idea to remain in the Union (93% voted in favour at Party Conference).

Since joining the EU, Johnson explained, the UK has strengthened the social dimension of its labour market, enabling workers to enjoy better and fairer working conditions. Ironically, in 1975, unions and workers were initially against the membership but since then, many have benefited from the common market and better employment standards brought through the European regulation.

The Labour Party's key message in campaigning for the Remain side is precisely to promote the social dimension of the EU, which the government and Conservative MPs do not wish to highlight.

However, the challenge remains ambitious. According to Johnson, there are still a number of industrial cities and rural areas to be reached in order to counter the Leavers' 'fear-based' campaign, including UKIP which is gaining ground in these areas.

The discussion was moderated by the Legatum Institute's Cristina Odone.