In recent days, presidential hopeful Donald Trump has become one of the most divisive and controversial figures in America, earning global condemnation with his incendiary comments on "the massive Muslim problem" and his call to ban all Muslims from entering the US.

A petition has been signed by more than 420,000 people, calling for a ban on the business magnate entering the UK because of his use of "hate speech" - and a White House spokesman said that his right-wing rhetoric "disqualifies him from serving as president".

Some have suggested he is pandering to a conservative audience; expressing extreme views to play into a narrative spurred by recent terror attacks carried out by Isis. Yet Mr Trump has insisted his comments are "not racist", saying UK politicians should be "thanking" him "instead of pandering to political correctness".

We asked a body language specialist to give us his expert opinion on whether Donald Trump, who has expressed many of his controversial views openly at speeches and rallies across America, completely believes everything he says.

Darren Stanton said: "When i first begin to analyse someone behaviour, be it for a generalised view of overall performance or indeed to spot signs of deceit, I do research on the individual so I view as much footage as I can of the person to establish what we call a baseline.

USA: Trump calls for Muslims to be banned from entering US

"I look at the speed of a persons breathing, identify what is normal for them, then watch the subtle changes in someone's chest. I also listen to the pitch, speed and tone of someone's voice. It's pretty well established that when someone is under extreme pressure from being discovered in a lie, or speaking about a topic in which they have little or no confidence, their pitch goes up, their speed may even increase or their voice may crack.

"I look at the person's face - their cheeks, neck, earlobes and nose are all areas that can be affected by the body's ‘flight or flight' response to stress. We've all heard the expression: "the blood drained from their face", or, "they were white as a ghost" - this is an example of that process.

"It has also been discovered that although there are many cultural differences in body language or customs, facially, the face generally only exhibits seven basic expressions of emotion which are consistent worldwide. These are:

Happiness

Sadness

Anger

Surprise

Fear

Contempt/Moral superiority

Disgust

"These are unconscious, fleeting expressions of emotion that flash for less than a fifth of a second. If, for example, a colleague congratulated you on your promotion, but then flashed a "disgust" micro-expression, we could conclude happiness for you was not the true emotion.

"I'm also interested in how animated a person is is terms of their facial expressions, voice and hand gestures. If their normal pattern of behaviour is interrupted by any inconsistent behaviour, this is what we call "leakage" - the body is streaming out the true intent.

"After analysing Mr Trump in great detail on his performance in relation to the topic of banning Muslims from the US, my conclusion is that this is a true belief he has - he is not just saying it to court the media or as a publicity stunt.

Donald Trump's most controversial quotes Show all 14 1 /14 Donald Trump's most controversial quotes Donald Trump's most controversial quotes On Isis: "Some of the candidates, they went in and didn’t know the air conditioner didn’t work and sweated like dogs, and they didn’t know the room was too big because they didn’t have anybody there. How are they going to beat ISIS?" Getty Donald Trump's most controversial quotes On immigration: "I will build a great wall — and nobody builds walls better than me, believe me —and I’ll build them very inexpensively. I will build a great, great wall on our southern border, and I will make Mexico pay for that wall. Mark my words." Reuters Donald Trump's most controversial quotes On Free Trade: "Free trade is terrible. Free trade can be wonderful if you have smart people. But we have stupid people." PAUL J. RICHARDS | AFP | Getty Images Donald Trump's most controversial quotes On Mexicans: "When Mexico sends its people, they’re not sending their best. They’re sending people that have lots of problems. They’re bringing drugs. They’re bringing crime. They’re rapists." Getty Donald Trump's most controversial quotes On China: "I just sold an apartment for $15 million to somebody from China. Am I supposed to dislike them?... I love China. The biggest bank in the world is from China. You know where their United States headquarters is located? In this building, in Trump Tower." Getty Images Donald Trump's most controversial quotes On work: "If you're interested in 'balancing' work and pleasure, stop trying to balance them. Instead make your work more pleasurable." AP Donald Trump's most controversial quotes On success: "What separates the winners from the losers is how a person reacts to each new twist of fate." Donald Trump's most controversial quotes On life: "Everything in life is luck." AFP Donald Trump's most controversial quotes On ambition: "You have to think anyway, so why not think big?" Getty Images Donald Trump's most controversial quotes On his opponents: "Bush is totally in favour of Common Core. I don't see how he can possibly get the nomination. He's weak on immigration. He's in favour of Common Core. How the hell can you vote for this guy? You just can't do it." Reuters Donald Trump's most controversial quotes On Obamacare: "You have to be hit by a tractor, literally, a tractor, to use it, because the deductibles are so high. It's virtually useless. And remember the $5 billion web site?... I have so many web sites, I have them all over the place. I hire people, they do a web site. It costs me $3." Getty Images Donald Trump's most controversial quotes On Barack Obama: "Obama is going to be out playing golf. He might be on one of my courses. I would invite him. I have the best courses in the world. I have one right next to the White House." PA Donald Trump's most controversial quotes On himself: "Love him or hate him, Trump is a man who is certain about what he wants and sets out to get it, no holds barred. Women find his power almost as much of a turn-on as his money." Getty Images Donald Trump's most controversial quotes On America: "The American Dream is dead. But if I get elected president I will bring it back bigger and better and stronger than ever before and we will make America great again." GETTY

"His micro-expressions, voice pitch, facial gestures and hand gestures all remained consistent with his baseline behaviour.

"Even is a person is well-versed in speaking publicly, most of these gestures are unconscious processess - meaning that even if a person were a good liar, it would be very difficult indeed to maintain the behaviour I observed.

"A gesture Mr Trump uses quite a lot is the "open palm gesture", which is said to be a sign of openness and honesty. It's like saying, "look, I have nothing in my hand to hurt you."