'Grateful': Gigi Hadid welcomes baby girl with Zayn Malik

LOS ANGELES -- Model Gigi Hadid and her musician boyfriend Zayn Malik took to social media to celebrate the arrival of an infant girl, with dad saying he's "grateful" and "thankful."

"To try put into words how I am feeling right now would be an impossible task. The love I feel for this tiny human is beyond my understanding. Grateful to know her, proud to call her mine," Malik wrote on Twitter.

He shared a black and white image featuring Malik and their daughter holding hands. Hadid also shared a similar photo on Instagram, with the caption: "Our girl joined us earth-side this weekend and she's already changing our world. So in love."

Neither parent revealed the baby's name.

The supermodel confirmed her pregnancy in April. It is Hadid's first child with boyfriend Malik, a former member of One Direction.

Hadid, 25, and Malik, 27, have been dating off-and-on for several years. She has become one of the world's most in-demand models and he was the first to leave One Direction to set out as a solo artist.