A waiter has spoken out about what happened after management allowed more than 600 guests at a wedding reception, which is in violation of current NSW COVID-19 restrictions.

Norman, who's worked at the Imperial Paradiso in Fairfield, said that employees were "incredibly concerned" they'd get in trouble despite having no idea management breached restrictions until the hordes of guests arrived.

“I was really worried about getting a personal fine,” he told NCA NewsWire.

“I didn’t know the amount of people who were coming and I don’t control the number of people, I’m not a manager.

“We all knew once (we saw the guestlist) but as a normal employee if I said anything it wouldn’t have worked.

“It was out of my hands.”

NSW Police confirmed on Monday that the venue had been fined $5,000.

Norman said things were tense as soon as police arrived, as staff were told to get in the kitchen and stay there.

“The chefs were really upset too,” he said.

“Even the band, I could hear them talking, and they said ‘let's eat dinner and leave’.”

NSW Deputy Premier John Barilaro has warned that the breach could have drastic flow-on effects for the larger community.

“Firstly can I say when you have a deliberate act like the venue operators – normally we thank businesses that are working hand in glove with government in relation with dealing with the pandemic, in this scenario and this case we got an example of someone who's done it bloody wrong,” he said.

“He puts his own business and that business’s reputation at risk, the sector at risk, the broader economy and jobs, and worse the health of this state.”