Niall Horan 'self-help guides'

Niall Horan is reportedly determined to "conquer" his problems with claustrophobia.

The One Direction charmer has openly admitted to a fear of small spaces in the past and has spoken about the struggles he sometimes faces on the band's tour bus.

Now friend say 20-year-old Niall has taken action over the phobia and is consulting self-help books on a daily basis.

"Niall really wants to conquer this problem once and for all. He's essentially practising amateur psychology at the moment and is getting through three books a week," an insider revealed to British newspaper Daily Star.

"The self-help books are teaching him how to manage crowds with various coping techniques. He has stacks of them by his bed and they're really making a difference to his state of mind."

At the end of last year Niall got stuck in an elevator, which was packed full of other people.

He took to his Twitter account to tell fans about the scare.

"Needed a few minutes to myself! 8 of us got stuck in a tiny lift! Well I was freakin out! My heart is still thumping now!" he posted to his 17.1 million followers.

"That wasn't fun! Claustrophobia is a terrible thing! and people tellin ya t calm down is worse hahha (sic)."

One thing Niall won't be worrying about at the moment is his bank balance.

It was reported earlier this week that One Direction are set to earn a cool billion dollars this year, thanks to their 2014 world tour, Where We Are.

The 88-dates of stadium shows kick off in April in Colombia and will see the boys travel for the majority of the year, taking in Europe, North America and Latin America.