Dilling, who was previously head chef at the two-Michelin-starred Greenhouse restaurant in Mayfair, confirmed the opening on Instagram, saying he couldn't wait to welcome guests.
"It is with great excitement and emotion I announce the opening of my flagship restaurant, Alex Dilling at Hotel Café Royal, in the iconic Hotel Café Royal," he wrote.
"This gastronomic restaurant will be one built around generosity, impeccable product and French technique.
"I have dreamt of this moment for many years and to see it come to fruition leaves me speechless.
"Thank you to all involved in this ambitious project."
Located on the first floor of the Hotel Café Royal, the restaurant will hold 34 covers.
Details of the menu have yet to be released, but the hotel's website says the cooking 'will primarily focus on showcasing gastronomic French classics through meticulous and unique cooking techniques'.
Reservations will be open from 15 June.
Dilling joined Greenhouse as executive chef in August 2018, having previously run Helene Darroze's restaurants in London and Paris.
He led the restaurant, which was owned by industry tycoon Marlon Abela, until its closure in the summer of 2020 amid the first national Covid-19 lockdown.