The EU referendum campaign has taken a light-hearted turn after Britain Stronger in Europe (BSE) released a Facebook video mocking prominent Eurosceptics. The short film makes fun of Ukips only MP Douglas Carswell, Eurosceptic firebrand Nigel Farage, Vote Leave chief executive Matthew Elliott and Conservative MEP Dan Hannan, among others.

The video seems to show contradictory statements from the politicians about what the UK would be like after a Brexit. No one knows what Britain out of Europe would look like – not even those who want us to leave, the films caption said.

The video comes ahead of a debate between the co-founder of Leave.EU Arron Banks and Will Straw, BSEs executive director. The pair are expected to clash at the Foreign Press Association in London on 7 January. The event will follow a similar debate in October 2015 when Straw took on Vote Leave campaign director Dominic Cummings.

David Cameron still has not set a date for the referendum, but he has promised to hold the historic ballot before the end of 2017. The latest major development ahead of the vote was the prime ministers decision to grant his ministers a free vote on the issue. The move means Eurosceptic ministers can back a Brexit and keep their government positions after Cameron has finalised his renegotiation deal.

Meanwhile, IBTimes UK exclusively revealed on 6 January that Leave.EU has claimed to sign up more than 600 Conservative councillors for their campaign. The group is contending Vote Leave to be assigned the official Brexit campaign nomination from the Electoral commission. The latest opinion poll from YouGov for The Times, of more than 1,500 people between 17 and 18 December, put leave one point ahead of remain (42% versus 41%, respectively).