Nigel Farage has been accused of resorting to xenophobic fear tactics after unveiling a "disgusting" Brexit poster showing a huge queue of non-white migrants on the borders of the European Union.

Politicians from across the political spectrum joined forces to condemn the campaign tactic, which they said exploited the misery of the Syrian refugee crisis in the "most dishonest and immoral way".

The Ukip leader dismissed suggestions the poster was racist and insisted very few people who came into Europe last year would qualify as genuine refugees.

But Conservatives, Labour, Liberal Democrat and Green Party MPs attacked Mr Farage for resorting to "small-minded fear tactics".

And Scotland's First Minister Nicola Sturgeon said the poster, which shows people crossing between Croatia and Slovenia to a refugee camp, under a warning that the EU is at "breaking point", is "disgusting".

Labour's Yvette Cooper said: "Just when you thought Leave campaigners couldn't stoop any lower, they are now exploiting the misery of the Syrian refugee crisis in the most dishonest and immoral way.

"Europe didn't cause the Syrian refugee crisis, and pulling out of the EU won't stop people fleeing conflict and persecution by Isis and the Assad regime."

Green Party MP Caroline Lucas said: "Using the innocent victims of a human tragedy for political propaganda is utterly disgusting. Farage is engaging in the politics of the gutter.

"The refugee crisis has not been caused by the EU. It is a common challenge that all countries must deal with effectively and humanely - and that is far more possible inside the EU than out."

Lib Dem MP Tom Brake said: " It's a shame that instead of engaging on the issues, Farage and his cronies have resorted to small-minded fear tactics and xenophobia."

Conservative MP Neil Carmichael said: "Distasteful propaganda like this can only make our immigration challenges worse, not better, and damage community cohesion in Britain."

Mr Farage launched the poster with a battlebus tour through Westminster, followed by 10 vans plastered with the image.

Islamic State (IS, also known as Isis) are exploiting the migrant crisis to flood the continent with terrorists, he claimed.

"This is a photograph, an accurate, un-doctored photograph, taken on October 15 last year following Angela Merkel's call in the summer and, frankly, if you believe, as I have always believed, that we should open our hearts to genuine refugees, that's one thing," Mr Farage said.

"But, frankly, as you can see from this picture, most of the people coming are young males and, yes, they may be coming from countries that are not in a very happy state, they may be coming from places that are poorer than us, but the EU has made a fundamental error that risks the security of everybody."

Told the people were refugees, he said: "You don't know that - they are coming from all over the world.

"If you get back to the Geneva Convention definition, you will find very few people that came into Europe last year would actually qualify as genuine refugees."

He added: " When Isis say they will use the migrant crisis to flood the continent with their jihadi terrorists they probably mean it."

Mr Farage said he was "feeling better about things than I was two weeks ago" about the prospect of victory for the Leave campaign.

"The Leave side now really are in with a very serious chance," he added.