A Tokyo restaurant on Monday began serving a sumptuous new take on the lowly hamburger: for a little under $1,000, diners are treated to a towering feast of giant patties covered with premium wagyu beef slices, topped with foie gras and black truffles and sandwiched between colossal golden-dusted buns, all to mark the upcoming coronation of the Asian country's new emperor.

The football-sized whopper – which weighs a whopping 3 kilograms (6 pounds), sports a diameter of 25 centimeters (10 inches) and is 15 cm tall – is set to spoil guests at the Oak Door steakhouse in Tokyo's Roppongi district until the end of June in celebration of the new Imperial era, Reiwa, and the long Golden Week (a succession of several national holidays).

The giant burger is priced at a whopping 100,000 yen ($903) and comes with a "1-kg beef patty, lettuce, tomatoes, onions, cheddar cheese, Wagyu beef slices, foie gras, freshly-shaved black truffles, gold-dusted buns and a side of triple-cooked giant fried potatoes," the restaurant said on its website.

The show-stealer one-stop feast will be available from Apr. 1 to Jun. 30.

"As a fourth-generation Japanese, I am honored to witness this exciting time of change in the Imperial era while working in Japan. While I was thinking how I could contribute to this once-in-a-lifetime opportunity, I came up with this idea of Golden Giant Burger. In celebration of this special occasion in Japan, we consider using gold as a traditional ingredient to present this burger for the enjoyment of our dearest guests," chef de cuisine Patrick Shimada said.

The restaurant will also serve a regular-sized golden burger, from Apr. 5, priced at JPY 20,000.

"Both topped with foie gras, wagyu, black truffles and sandwiched between two golden-dusted buns. Let these indulgent burgers be the perfect choice for celebration!" it said.

The regular burger boasts a juicy beef patty topped with foie gras, wagyu beef slices and black truffles, although this one is finished off with Madeira sauce and goat cheese.

"The burger offers an enhanced scent of truffles and a good balance of sourness," the restaurant said.

The Japanese government had announced Monday that the name of the new imperial era will be "Reiwa," a combination of two characters inspired by an 8th-century classic poem.

Crown Prince Naruhito, 59, is set to ascend the Chrysanthemum Throne on May 1 after the abdication of his father Emperor Akihito on Apr. 30 due to old age, ending the Heisei era.

It is the first such instance of abdication to have occurred to the Japanese throne in more than 200 years.

The term Reiwa is inspired by a poem from the Manyoshu collection, perhaps the oldest existing compilation of Japanese poetry from around the eighth century, and was one among the five shortlisted, announced government spokesperson, Yoshihide Suga at a press conference.

The reign of Akihito, 85, has lasted three decades – starting in Jan. 1989 – and is called the "Heisei" era, a term formed by two characters that may be translated together as "achieving peace."

Other names of the former Japanese eras are "Meiji" (enlightened government) that started in 1867 when the throne was occupied by Emperor Mutsuhito, "Taisho" (great legitimacy) from 1912 marking the reign of Emperor Yoshihito, and "Showa" (peace and harmony) from 1926 marking the reign of Emperor Hirohito.