Kim and Kanye's third baby arrives

Kim Kardashian West and her husband Kanye West have become parents to a baby girl, delivered via a surrogate.

Kardashian West announced the news on her official website, in a post that revealed the weight of the newborn was seven pounds and six ounces.

"Kanye and I are happy to announce the arrival of our healthy, beautiful baby girl," wrote the reality TV star.

"We are incredibly grateful to our surrogate who made our dreams come true with the greatest gift one could give."

She said her other two children, four-year-old North and two-year-old Saint, were "especially thrilled to welcome their baby sister."

Kardashian West previously revealed she had decided to use a surrogate after doctors warned of serious health risks if she became pregnant again.

Kim's sister Khloe confirmed in December that she was pregnant with her first child, while it has been widely reported their half-sister Kylie Jenner is also expecting.

In her post, Kardashian West said the new arrival - whose name is not yet known - was born on 00:47 on Monday.