Nigel Farage pulled out of last night's final, crucial television debate on today's EU referendum so he could 'have dinner with his son', it has been revealed.

Farage, who has campaigned for the UK to leave the European Union his whole political life, told Channel 4 he would not be attending the evening's debate due to 'family reasons'.

The announcement was met with surprise, with many expressing concern for Farage and his family as many believed only something truly terrible would make the politician pull out of the key debate.

However, it has now emerged that Mr Farage had simply decided to go to dinner with his eldest son, Sam.

Speaking outside his home this morning, he refused to elaborate on his decision not to attend, repeating only that it was 'for family reasons'.

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Nigel Farage outside his home as he heads off to vote this morning. But he ducked out of a TV debate on the eve of the referendum he has been demanding for years

The UKIP leader had a meal with his son Sam yesterday evening, rather than join a discussion on Channel 4

A source said: 'He hadn't seen him for nine months so it was between that or being on against the founder of Ukip who calls him racist. It was a no brainer.'

Ukip founder Alan Sked, who took part in last night's debate, has criticised the way Farage has run the party, calling it a 'Frankenstein's monster'.

It is understood Farage hadn't seen his son for so long because Sam, who works as a manager for accounting firm KPMG, has been away in South Africa.

Farage declined to comment on the no-show this morning but tweeted message to his followers, calling on them to 'take back control of our country'.

Both Farage's sons from his marriage to his first wife, Grainne, work in the City. He also has two young daughters from his current marriage to wife, Kirsten.

Sam, 27, went to Dulwich College in south London, as his father did, before getting a degree and masters at Exeter University. He and his father have previously been pictured together at events.

Farage recently told ITV: 'I've got a son who works for one of the corporates and he's been told: "You must vote to remain part of this otherwise terrible things will happen".'

Farage was scheduled to appear alongside a number of high profile guests from both sides of the campaign, including former Labour spin doctor Alastair Campbell, Tory peer Michael Heseltine, former Tory MP Louise Mensch - and Delia Smith, who slammed Ukip's most recent Brexit poster as 'anti-human'.

The popular television cook called the unveiling of the poster - which which depicts a snaking line of hundreds of immigrants arriving in Europe - as the 'darkest moment' of the EU campaign.

Ms Smith, speaking during the first segment of the programme which largely focused on how each side had run their campaigns, said: 'It's got darker and darker.

'I really think its darkest moment was when we saw the poster. I do not think it was just offensive. It was anti-human.'

It has since emerged that the 'family reason' was a dinner with his oldest son, Sam (pictured right)

Television cook Delia Smith was at the debate, sitting with 'Remain' supporters

Sheila Hancock, pictured with Simon Schama, Steve Hilton and Selina Scott, won praise from fellow Remain campaigners for her impassioned defence of the European Union during the debate

Despite the criticism of his campaign, Farage was upbeat about the chances of a leave vote this morning.

Speaking outside his home in Kent after collecting his newspapers, he said: 'I do think we are in with a very strong chance, I do genuinely. But it's all about turnout and those soft remainers staying at home.'

I'VE WAITED MY ADULT LIFE FOR THIS MOMENT, SAYS UKIP LEADER As he headed to the polling station this morning, Farage joked that he would have 'crawled uphill over broken glass to cast a vote'. He said he'd 'waited all my adult life' for the EU referendum and quipped that he'd 'finally made my mind up' to vote leave. He said: 'I first got involved in this in Eurosceptic politics in 1991 so I've stood in more elections than I care to remember - all trying to argue that there is something wrong with our relationship with the EU. 'The first big victory was not going in the Euro, and I hope this will be the ultimate one.' Advertisement

Farage had refused to apologise for his controversial 'breaking point' immigration poster earlier yesterday, despite suggestions by his party that he had.

Speaking in central London, Mr Farage said: 'I apologise for the timing and I apologise for the fact that it was able to be used by those who wish us harm.

'But I can't apologise for the truth. And after all, this was a photograph your newspaper carried, this was a photograph that all newspapers carried, it is an example of what is wrong inside the European Union.'

Ukip had offered their MEP Steven Woolfe to take the place of Mr Farage the broadcaster declined, the party said.

Ahead of the event, Alastair Campbell tweeted that Farage had 'bottled it'.

The debate was one of the last opportunities for the Remain and Leave camps to put forward their arguments before polls open at 7am today.

The 90-minute discussion, hosted by Jeremy Paxman, addressed the key issues of the referendum, including the economy, immigration, sovereignty and security.

Delia Smith said the unveiling of this poster was the 'darkest moment' of the EU campaign

Selina Scott, right, said she would never bother voting again if 'Leave' were not successful on Thursday

However, tensions between the two sides often boiled over, and at times it seemed Paxman was struggling keep his rolling stage of panelists on topic.

At one point, a visibly annoyed Paxman told Eurovision winner Sandie Shaw: 'We are trying to discuss something else, and you are going on about music.'

The panelists were equally tetchy as they continually spoke over each other.

When Simon Schama tried to interrupt Steve Hilton, the former Tory adviser snapped: 'That's a little bit rude to interrupt someone when they've just started.'

Mr Hilton - who used to work as David Cameron's director of strategy - was later called out as a hypocrite for having a go at 'un-elected bureaucrats'.

He was not the only one, former chancellor and Leave campaigners Nigel Lawson's fears over Britain becoming a 'colony' of a United States of Europe were met with the point he lives in France.

At one point, Selina Scott - a Leave supporter - suggested that if the referendum did not end with the UK leaving the EU, she would never vote again.

'Why should I bother?' she asked.

Meanwhile, Sheila Hancock put forward an impassioned defence of the EU, what it had done for peace, and said people of her age should vote with their children and grandchildren in mind.

'We will always be British,' she added - leading Alex Salmond to note later: 'Sheila Hancock should have been in charge of the campaign.'

Alex Salmond (left) and Alastair Campbell during the Channel 4 EU referendum debate. Salmond clashed with writer Toby Young, who suggested Scotland would end up in a worse position than Greece should it chose to split from England following today's referendum

Nigel Lawson said he feared Britain could be turned into a 'colony' of the 'United States of Europe'

He was scheduled to appear alongside a number of high profile guests from both sides of the campaign, including former Labour spin doctor Alastair Campbell, Tory peer Michael Heseltine and former Tory MP Louise Mensch

Fellow Remain supporter Tory Michael Heseltine was also full of praise for Ms Hancock.

'I happen to share with her the age of 83,' he said. 'And what we know is what it was like to be alone in 1940.'

Toby Young and Salmond also clashed on the evening, with the writer telling the SNP politician that a second referendum on Scottish independence would see them 'become the next Greece'.

The idea of a second referendum has been discussed, should Scotland vote overwhelmingly to remain, and the rest of the UK to leave.

In the end, 52 per cent the audience, which was split into 50 Remain, 50 Leave and 50 undecideds, voted to back staying in Europe.