Hawai'i celebrity chef Sam Choy plans to close one of his two O'ahu restaurants — the upscale flagship on Kapahulu Avenue — and relocate employees and some menu items to his larger and more casual restaurant in Iwilei.

The restaurant, which opened in 1995 at 449 Kapahulu Ave. not far from the edge of Waikiki, will close Sunday night.

A restaurant spokeswoman said rising costs were eating away at operating margins that prompted the consolidation move.

"Sam Choy's Diamond Head had a great run and we introduced both kama'aina and visitors to what is now known as Hawai'i regional cuisine," Choy said in a written statement.

The Iwilei restaurant, which opened in 1997 on Nimitz Highway in a converted warehouse, will undergo a renovation in the fall and be renamed from Sam Choy's Breakfast, Lunch, Crab & Big Aloha Brewery to simply Sam Choy's. The restaurant will continue to serve breakfast, lunch and dinner.

All 25 employees from the 175-seat Kapahulu restaurant, which is open only for dinner and Sunday brunch, will be offered jobs at the Iwilei restaurant, which employs 125 and seats 550.

The filming of the chef's local TV cooking show also will be relocated from the Kapahulu restaurant to the Iwilei location.

Gift cards valid at Sam Choy's Diamond Head will be accepted at the Iwilei restaurant.

Choy said he is discussing possibilities for creating a new restaurant concept to fill the Kapahulu restaurant space, which is in a building owned by James Lee, a partner in Choy's restaurants.

Choy, born and raised on O'ahu and educated at Kapi'olani Community College, opened his first restaurant in 1981 in Kailua, Kona, on the Big Island after working in several Hawai'i hotel restaurant kitchens. The Big Island restaurant closed in 2004.

Choy also opened and closed a Maui restaurant, but still operates one in Guam. The chef also has three small franchised eateries in Japan.