He pulled out of Capital FM's Summertime Ball last year, later revealing his absence was due to anxiety. The former One Direction star has also cancelled some gigs in Japan, after initially rescheduling them.

According to The Sun newspaper, a variety of reasons have been given, including that there was "a change in the recording schedule" and that Malik is too busy "planning his debut world tour", reports dailymail.co.uk.

"If he never performs, there's a danger his solo career will flop," said a source. 

Hadid said in a statement to aceshowbiz.com that she wants to end her relationship with the Former One Direction member soon as she is unable stand his dependent behaviour. 

The 24-year-old singer's struggle with anxiety is taking a toll on their relationship and she feels "suffocated" by him.

"Zayn still gets incredibly worked up over every little thing and it's really wearing Hadid out. He's become dependent on her, and she feels trapped. Everyone around her is convinced she'll end it by the end of summer," a source said

The 24-year-old, who is dating American model Gigi Hadid, feels he has lost his personal space, reports femalefirst.co.uk.

"It's a really weird world. I don't think there's anywhere I could be anonymous now," Malik told Evening Standard newspaper.

"In New York (where Gigi is based), you can sometimes get out in the early hours of the morning for a walk.

According to a source, Malik was forced into working with Swift on the "Fifty Shades Darker" soundtrack, which released earlier this year and became an instant hit, reports radaronline.com. 

"Zayn loved the song and wanted it for himself. He was desperate to record it as a solo track and thought it would be a real career boost," the source said.

"It has all of the high notes he can reach and was perfect, but movie bosses said it has to be a collaboration and wanted him to work with Taylor," the source added.