The 22-year-old singer pulled out of the group's current tour on Thursday (19Mar15) and jetted back to the U.K. after a doctor signed him off with stress.

It followed a storm of publicity about his private life after the star, who is engaged to Little Mix singer Perrie Edwards, was pictured apparently holding a young woman's hand during a night out in Thailand.

The four remaining members assured fans they will continue the tour in Asia without Malik, and they performed as a four-piece in Manila, Philippines on Saturday.

In a show of support for their troubled bandmate, the pop stars avoided introducing themselves as One Direction and simply used their first names to thank the crowd.

Malik is expected to rejoin the band for a show in Cape Town, South Africa on 28 March (15).

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