An American weekend news anchor has been suspended after being caught on camera swearing live on air - before starting his very first broadcast.

NBC's A.J Clemente was captured muttering a homophobic slur into his microphone as he joined co-host Van Tieu to present the North Dakota News.

In the 30-second clip, posted on shock media site, he can be heard saying "Gay f**king sh*t" before Tieu introduces him to viewers ahead of the evening report.

She says: "Good evening, I'm Van Tieu, you may have seen our newest reporter A.J on Envy and CE North Dakota News. He will be joining North Dakota news as my co-anchor. Tell us a little about yourself A.J."

Clearly embarrassed about the gaffe, Clemente struggles to respond and eventually manages to say: "Um thanks man, I'm very excited - I graduated from West Virginia University and I'm used to, um being, you know, from being in East Coast."

The bizarre broadcast, which has since gone viral, has provoked a huge response from the online community.

One viewer said: "His career on the news is over before it begins."

"I can't help feeling sorry for him, it seems no one told him they were about to go live on air or he was so nervous he didn't pay attention," another wrote.

A spokesperson for the NBC station has since apologised for the slip-up and confirmed Clemente's suspension.

"I want to apologise for an incident that occurred prior to our early newscast this evening, when one of our employees used profanity on the air,' Monica Hannan, news director for the NBC station, wrote on the KFYR Facebook page.

"He did not realise his microphone was on, but still, that's no excuse. We train our reporters to always assume that any microphone is live at any time. Unfortunately, that was not enough in this case. We can't take back what was said.

"The person involved has been suspended until we resolve the situation. All we can do at this point is ask for your forgiveness, and I can offer my personal assurance that I will do my best to ensure that nothing like this ever happens again under my watch."