World leaders attending the Group of Seven summit in Hiroshima have been treated to a belt-expanding tour of local gastronomical delights with a host of menus showcasing the best of Japanese fine dining.

Among some of the more luxury ingredients the cohort has sampled so far were fresh Japanese oysters, hiba beef and sea urchins -- some of the country's most prized exports -- prepared in the style of a kaiseki meal, a meticulously prepared, exquisitely served and, usually, very expensive style of multi-course meal.

World leaders of G7 nations Japan, Germany, France, Canada, Italy, the United Kingdom and the United States have converged in the southern city of Hiroshima, and are expected to work on a unified response to an increasingly assertive China and Russia's aggression toward Ukraine until Sunday.

What's on their plate away from vital diplomacy has sparked curiosity as the summit's hosts seize the opportunity to showcase the dining prowess of Japan, the home of sushi, ramen and omakaze -- a phrase that loosely means "I'll leave it up to you" that allows chefs to delight patrons with what they think is best.

Flying in on Friday, world leaders were treated to a kaiseki working diner at one of the region's most exclusive ryokans -- a traditional Japanese hotel -- on Miyajima island, after visiting the Hiroshima Peace Memorial Museum.

They were served by Mamoru Sakamoto, head chef at Miyajima no Yado Iwaso, who is a master in traditional Japanese cooking and packed the one-and-a-half-hour dinner with dishes sourced from across Hiroshima prefecture and the Seto Inland Sea.

The meal began with sake-steamed oysters, served with caviar, accompanied by Japanese tiger prawns marinated in shuto, a sauce derived from fermented entrails of bonito in sake, honey, and mirin rice wine.

Leaders were also served sea bream with Japanese matsutake mushrooms, simmered stonefish and slipper lobster.

Next came famously marbled beef sourced from Hiroshima -- known as hiba beef -- served alongside red sea urchin and eggplants, complemented by a selection of sparkling sake and red wine.

Japanese Prime Minister Fumio Kishida will host the working lunch Saturday at the Grand Prince Hotel in Hiroshima, where world leaders will get a state of marinated salmon and scallop sashimi as starters.

For the main, they will be served with homegrown chicken and locally sourced mussels, according to the menu seen by CNN.

Meanwhile, British leader Sunak tried his hand at making okonomiayki, a traditional savory pancake dish.

And for those still hungry, Sunak and other world leaders will have plenty more opportunities to sample Japanese cuisine before they begin to depart from Sunday.