Solange Knowles was left red-faced on live TV after she berated a U.S. news anchor for her unprofessional line of questioning - despite being asked them before the interview went live.

The singer was asked by anchors on Las Vegas news show Kvvu if they could mention her more famous sibling Beyonce Knowles and her husband Jay-Z in their mid-morning interview.

Knowles' publicist quickly shot the host down - insisting they must keep their line of questioning directed at Solange, according to TMZ.com.

And, despite the news channel agreeing, Knowles angrily confronted the female host, branding her interview technique "unprofessional" - even though the questions hadn't been shown to viewers.

She told the shocked presenter, "I just have to say that wasn't a very professional introduction before. Please don't tie me in with my family and questions about my brother-in-law."

The confused anchor apologised before producers on the show made Knowles aware that viewers had not seen the questions about Jay-Z.

It is not the first time Knowles has shown her irritation when asked about her more famous sister.