Arnold Schwarzenegger doesn't suffer any self-doubts.

The 72-year-old actor - who is one of the best-paid stars in Hollywood - has always had clear ambitions in mind and he's never allowed setbacks to distract him from his long-term vision.

Schwarzenegger - who was a professional bodybuilder before turning to acting - told The Sun newspaper: ''I have never had any dark moments.

''I am very lucky that I had a very clear vision about what I wanted to achieve and accomplish. Most people don't have that.

''That's why most people are searching for some answers, for some truth. They read self-help books on how to be happy. I don't have that.''

Earlier this year, Schwarzenegger claimed that US President Donald Trump is envious of him - despite their ongoing feud.

The high-profile duo have exchanged insults over recent years, but the actor claims that, deep down, Trump actually admires him.

Schwarzenegger said: ''I think he really ... he's in love with me. That's the reality of it. With Trump, he wants to be me.''

Asked whether Trump's fearful of him, Schwarzenegger replied: ''I don't think he fears me.

''But I remember that in the old days, when we went to the wrestling matches, the way he admired people with bodies, and the way they would jump around in the ring, and to perform physical stunts and stuff like that - he had great admiration for that. And the showmanship - he had great admiration for that.

''He asked me, 'How do you do that, with the movies? I mean, it's so believable.'

''He drilled down to specific questions that fascinated him. It was about, 'How do you sell something? Like, a scene. How do you go and act out a scene so that I get affected emotionally?' He was fascinated by that.''