Acclaimed Sydney chef Josh Niland and restaurateur Julie Niland have revealed ambitious plans to expand their seafood empire by taking over the recently refurbished Grand National Hotel in Paddington.

Niland says the historic watering hole will be transformed into a multi-dimensional hospitality hub boasting an opulent 45-seat restaurant, 15-seat private dining room, bar and boutique hotel.

The Grand National Hotel will become the new home of Nilands' hatted fin-to-tail seafood restaurant Saint Peter, which will close the doors to its Oxford Street location in early 2023.

"I'm really excited to have a generous dining room where I can welcome more people with open arms," Niland says.

The new a la carte Saint Peter restaurant will be illuminated by a skylight ceiling and feature an open kitchen, wood-fired grill and selection of fish charcuterie cabinets and displays.

While an opening date is yet to be announced, Niland hopes the project will be ready by the end of summer.

"It's going to be stunning. I'll have all the infrastructure I could ever imagine to be able to execute the vision of Saint Peter on a much grander scale," Niland says.

"The whole reason I cook, the whole reason I'm in hospitality, is because I love people and I love cooking for them. But since Saint Peter halved its capacity I've only been able to reach a handful of people each day.

"With this new opportunity we'll be able to reformat back into an a la carte experience where I can interact with guests and they can choose their own adventure."

The menu will continue to showcase Australia's leading seafood producers and Niland promises to maintain his "enthusiasm towards exploring what is possible with a fish".

Where punters once pulled up a stool to watch the footy at The Grand National, they'll soon be able to nestle into a booth or sit at Saint Peter's first bar. It's been a long time coming for Niland, who says he's always wanted a space for diners to relax with a drink before or after their meal.

"In the past we've never catered for that. As soon as people entered the doors at Saint Peter we got straight into it."

The bar will also become an extension of the restaurant, with a smaller and more accessible menu.

And when last drinks are called, not everyone will have to make the journey home: the Saint Peter team plans to open 14 high-end hotel rooms above the restaurant.

While Niland remains tight-lipped on the details of the hotel, he can't help but express his excitement.

"It was an offer too good to resist," Niland says. "It's an amazing thing, to have a restaurant with accommodation. For people who have travelled internationally or interstate, to have the option of having a room above where they intend to dine is fantastic."

Niland says this announcement was three-and-a-half years in the making.

"I've been working on this for so long, and in that time the handbrake has been pulled unpredictably so many times," he says. "But now there's a finishing line ahead of us."

As the couple prepares for the project to get underway, they have one more cause for celebration. The Basque Culinary Centre, one of the world's most revered culinary schools, has appointed Josh Niland as a board member. Niland becomes the first Australian to join the board, alongside the likes of Massimo Bottura and Rene Redzepi.

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