Nigel Farage was embroiled in a bitter public spat with the husband of murdered Jo Cox today over who was to blame for the deadly terror attack in Berlin last night.

The former Ukip leader said the lorry attack on a Christmas market in the German capital, which left 12 dead and dozens injured, was 'terrible news... but no surprise'.

'Events like these will be the Merkel legacy,' Mr Farage said today and even suggested the German Chancellor's open borders policy was the worst decision by a European politician since Hitler.

Brendan Cox, whose wife was brutally killed in the streets of her Yorkshire constituency in June, lashed out at his comments.

He told him: 'Blaming politicians for the actions of extremists? That's a slippery slope Nigel.'

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Nigel Farage, pictured on LBC radio today, said the lorry attack on a Christmas market in the German capital, which left 12 dead and dozens injured, was 'terrible news... but no surprise'

Brendan Cox, whose wife was brutally killed in the streets of her Yorkshire constituency in June, lashed out at Nigel Farage on Twitter

Brendan Cox, pictured in an interview in October, lashed out at Nigel Farage's comments, telling him it was a 'slippery slope' to start blaming politicians for extremism

Mr Farage hit back at Mr Cox as he continued the bitter public spat on the airwaves and also took a swipe at him for his pro-immigration views.

He told LBC: 'Well, of course, he would know more about extremists than me, Mr Cox, he backs organisations like Hope Not Hate, who masquerade as being lovely and peaceful but actually pursue violent and very undemocratic means.'

Mr Farage added: 'It's a terrible thing what happened to his family, with the murder of his wife, but he continues to be active in the political arena and as I say, given some of the organisations that he supports, I can't just stand here and say I'm not going to respond.'

This prompted angry replies from Mrs Cox's former colleagues in Westminster.

Chris Bryant, Labour MP for Rhondda MP, said the 'sheer nastiness of Farage sometimes takes my breath away,' while Tracy Brabin, who replaced Mrs Cox as MP for Batley and Spen, said: 'Beggars belief... A new low for Farage.'

The Hope Not Hate campaign threatened Mr Farage with legal action if he refuses to apologise for suggesting its supporters pursue violence.

Mr Farage, a longstanding opponent of immigration, said we should be more straightforward in laying blame for terror attacks.

He said: 'Frankly, people like Mrs Merkel ought to take responsibility for what's happened.'

The former Ukip leader added: 'Whenever these terrible things happen the response is 'well it's no one's fault, no one's responsible, these things just happen'.

'I'm sorry and I know I'll be condemned for it but I think in the case of Germany we ought to be a little more straightforward.

President-elect Trump also sent out a tweet saying the 'civilized world must change thinking'

A suspected radical Islamic extremist murdered 12 and injured dozens gathered at a Christmas market in Berlin last night

'The facts as we know them is that it's a 23-year-old from Pakistan who came into Germany this February.

'I have to say, I'm not even sure why someone from Pakistan qualifies for a refugee as opposed to being more of an economic migrant.

'But let's be honest about this, Mrs Merkel made one of the worst policy decisions I've seen from a European politician I've seen in the last 70 years when she unconditionally said in the middle of 2015: 'as many as want to come, can come'.

'There was no vetting, there was no checking and there were people like me standing up for months ahead of that saying we should not let our compassion imperil our safety and indeed our civilisation.'

Mr Farage's friend Donald Trump reacted to the horrifying events last night by vowing to 'eradicate' terrorists from the 'face of the earth'.

The president-elect, another fierce critic of Mrs Merkel's open borders policy, said it was a 'horrifying terror attack' and would push the US and its 'freedom-loving partners' to take on ISIS.

Dozens of ambulances and fire engines were sent to the scene in central Berlin at around 8.30pm local time

The deadly attack triggered a furious backlash against Angela Merkel's open borders policy

In Germany Mrs Merkel has faced an avalanche of public anger over her open-doors policy.

She has come under huge political pressure for allowing nearly a million people fleeing conflict and poverty in the Middle East and Africa to arrive in the country this year and last.

Last night the far-right anti-immigration Alternative for Germany (AfD) party lashed out at Mrs Merkel.

Jo Cox, pictured in Parliament last year, was murdered in her Yorkshire constituency in June

Senior party member Marcus Pretzell tweeted: 'When will the German state of law strike back? When will this cursed hypocrisy finally stop? These are Merkel's dead!'

Mrs Merkel has shifted her policy towards refugees and migrants to the right in recent weeks, including a speech in which she suggested stemming the number entering Germany and restricting the use of face veils.

Germany admitted almost 900,000 migrants in 2015 after deciding to allow in those who had made it to Hungary.

Although the numbers has dropped sharply in 2016, Mrs Merkel's CDU party has suffered internal strife and a string of poor election results.

Thomas Mair, who killed 41-year-old mother-of-two Mrs Cox as she arrived to hold a surgery in her Batley and Spen constituency in Yorkshire, was handed a whole life sentence in November.

Mair, 53, shouted 'Britain first' as he fired three shots at Remain campaigner Mrs Cox and stabbed her 15 times on the afternoon of June 16.

After Mair was jailed, Mr Cox said he had committed the 'most incompetent and self-defeating' act of terrorism.

Responding to Mr Farage's comments, the Hope Not Hate group said: 'We are aware of a serious and potentially libellous statement made about Hope Not Hate by Nigel Farage on LBC radio this morning.

'We have no idea on what Mr Farage bases his outrageous comments. Hope Not Hate has a proud history of campaigning against extremism and hatred.

'We will not be making any further comment until we have had the opportunity to consult with our lawyers.'