Zayn Malik is not happy that Matt Lauer questioned One Direction about the singer's supposed substance abuse problem during the band's appearance on the 'TODAY' show yesterday (Nov. 17).

While Liam Payne explained that Zayn's absence was caused by a "tummy bug," the veteran journalist asked if something more serious was going on, like a substance abuse problem -- which, of course, Liam denied. (And Niall Horan's face said everything.)

“I’m really angry and upset by what was said," Zayn reportedly told the Sun (quote via the Mirror). "I was really ill at the weekend, that’s why I couldn’t fly to America.” The Mirror reports that Zayn will once again join the boys on their 'Four' promo tour once he feels better.

A rep for the singer also spoke to the Mirror about Zayn's health, explaining:

"Zayn was taken ill after recording the Band Aid single at the weekend and was unfortunately not well enough to fly to the USA yesterday. He will join the band for promotion for the new album as soon as he possibly can."

Feel better, Zayn! And in the meantime, watch the band (yes, including Zayn) perform an acoustic version of 'Night Changes.' We've been losing our minds over this rendition all morning, so when we say it's good, we seriously mean it.

See Zayn Malik, Harry Styles + More Celebs' Yearbook Photos