Dokdo / Korea Times file

North Korea lashed out at Japan, Saturday, for its claim to Dokdo, two South Korean islets in the East Sea calling it a shameless act.

"The Japan sports world has reached the extremes in its shameless act designed to seize Tok Island, part of the inviolable territory of Korea, even in defiance of the sacred idea and spirit of the Olympic movement," a spokesman for the North's Olympic Committee said in a statement carried by the country's official Korean Central News Agency.

The statement comes amid a renewed row between Seoul and Tokyo over the latter's claims to the South Korea-controlled islets.

Japan's Tokyo Olympics Organizing Committee marked Dokdo islets as Japanese territory on its torch relay map posted on the official website of the summer Olympic games, set to begin next Friday.

"Political issues are inseparable from territorial issues, and it is shameless and groundless sophism to insist that it is just a geographical concept that part of Korea is marked as part of Japan," the North Korean statement said.

"The act of abusing the Olympic Games for realizing territorial ambition though they are supposed to promote friendship and harmony is a mockery of sportspersons all over the world and the desire of mankind for peace, and an intolerable provocation violating the sovereignty of the Korean nation," it added.

Seoul has also filed strong protests with Tokyo and the International Olympic Committee (IOC) regarding Japan's marking of Dokdo as its own territory, but both Tokyo and the IOC have done little to address the issue.

The spokesman for the North Korean Olympic Committee called the IOC's reaction "problematic."

"The International Olympic Committee's response to the wrong assertion made by the Tokyo Olympic Games Organizing Committee is also problematic," said the statement, noting the IOC had "categorically opposed" marking Dokdo as Korean territory on a flag used in the 23rd Winter Olympic Games held in PyeongChang, South Korea, in 2018.

North Korea is not taking part in the Tokyo Olympic Games due to concerns over the COVID-19 pandemic, which has seen the impoverished country impose a border shutdown since early last year. (Yonhap)