A 'minor issue' has kept Beyonce and her newborn twins in hospital longer than expected.

Beyonce’s twins have been kept in hospital for a week due to a “minor issue”, according to US media reports.

The singer, 35, and her husband Jay Z, 47, welcomed a baby boy and girl on Monday, TMZ confirmed.

Sources connected with the family told TMZ doctors do not feel comfortable releasing the mother and her little ones yet.

“Beyonce also remains at the hospital, but as far as we know she’s okay. The babies are expected to be okay as well,” says the TMZ website.

The superstar couple now has three children. Five-year-old Blue Ivy will be a big sister to the twins.

Beyonce’s dad, Mathew Knowles, welcomed the newborns in a Twitter message.

He posted a ‘happy birthday’ greeting, signed with love from Granddad, and captioned: “They’re here!”

In the past week Beyonce’s fans had grown suspicious that the birth of her twins had already happened.

Many are expecting her next post to be the most liked photo on Instagram.

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