Waiter punches female customer as intervening diners threatened with machete (GRAPHIC VIDEO)

A shocking video of a female diner being punched by a male waiter in a restaurant in Mexico has gone viral after it was shared online by a fellow customer.

The other customer claimed he was threatened by another restaurant employee with a machete when he tried to intervene in the altercation.

The footage, filmed at the Taqueria La Guelaguetza restaurant in Queretaro, central Mexico, shows a woman surrounded by several waiters in an apparent argument before being pushed to one side.

As the waiters walk away, the female diner confronts another member of staff who then punches her – and follows it up with two more blows.

Customers stepped in to break up the fight, but this led to one of the restaurant workers threatening to use a machete against them, according to Jose Abel Gonzalez, who posted the video on Facebook.

He said the woman had been drinking and become aggressive, throwing plates prior to the assault, but added: “I believe that nothing justifies the beating of a woman, whatever you do.”

The restaurant issued a statement on its Facebook page, apologizing for the incident and condemning the violence on its premises.

"The Guelaguetza is a public place where it allows access to any person regardless of their craft, religion, race, gender, disability, social or economic status,” it stated.

The waiter who punched the woman has been fired, while other staff members involved in the incident have been disciplined, according to manager Martín García.