(CNN) South Korea's choice of dessert for Friday's historic inter-Korean summit has left a bitter taste in Japan.
Tokyo has lodged a formal protest about the mango mousse planned for the dinner between President Moon Jae-in and North Korea leader Kim Jong Un because the dish features a map of the Korean Peninsula that includes a contested island that is claimed by Japan.
Japan's Ministry of Foreign Affairs said Wednesday that Kenji Kanasugi, director-general of the Asian and Oceanian Affairs Bureau, had told the South Korean Embassy that the inclusion of Takeshima, or Dokdo island in Korean, was "very regrettable" and "not acceptable."
Japan says that South Korea is illegally occupying the rocky islands that lie east of the peninsula, and it's an issue that has long soured relations between the two countries.
South Korean Foreign Minister Kang Kyung-wha brushed off the complaint during an interview on Thursday, telling CNN's Christiane Amanpour it was a "non-issue."
Images released by South Korea Wednesday show a similar map on the top of specially designed chairs which seat Moon and Kim when they meet at the southern side of the Demilitarized Zone that divides the two countries. The Japanese have complained about those as well.
Seoul has spared no effort in its preparations for the summit, the first time the leaders of North and South Korea have met in more than a decade.
In the room in the Peace House where they'll meet, the normal rectangular table has been replaced by an oval one. Moon's office hopes the shape will encourage the summit's participants to talk candidly.
Other design features focus on a shared history between the two countries, including incorporating elements of a Hanok, a traditional Korean house.
At the dinner after the summit, each course on the menu comes with a heavy dash of symbolism.
Guests will be served a dish from the hometown of the three South Korean presidents who will have hosted an inter-Korean summit.
They'll eat food from the Korean Peninsula's far north and south, including cold noodles, dumplings and barbecued beef. There will even be food sourced from the demilitarized zone itself.