Story highlights China's foreign ministry says Japanese diplomat "ignorant, unreasonable and arrogant"

Comments come after envoys from both countries invoked Voldemort, Harry Potter's enemy

Tensions have been strained after war shrine visit and escalation of island dispute

Unexpected and surreal turn of events bemuses internet users in both countries

Lord Voldemort, the arch-villain in the Harry Potter series of books and films, has played an unlikely cameo in a diplomatic feud between China and Japan.

China's foreign ministry spokeswoman on Tuesday accused a Japanese diplomat of being "ignorant, unreasonable and arrogant" after the two countries upped the stakes in their propaganda war by likening each other to the fictional evil wizard.

China's ambassador to the United Kingdom, Liu Xiaoming, first made reference to the character in an opinion piece published by Britain's Daily Telegraph last week.

It came in response to Japanese Prime Minister Shinzo Abe's December 26 visit to Tokyo's Yasukuni shrine , where convicted war criminals are honored along with other war dead.

The move incensed China, which suffered under Japan's military aggression in World War II, and regards the shrine as a symbol of Japan's imperial past

JUST WATCHED Japan's PM visits controversial shrine Replay More Videos ... MUST WATCH Japan's PM visits controversial shrine 04:26

"If militarism is like the haunting Voldemort of Japan, the Yasukuni Shrine in Tokyo is a kind of horcrux, representing the darkest parts of that nation's soul," Liu wrote.

In the best-selling series by British author J.K. Rowling, a horcrux is used by Voldemort to hide fragments of the soul in a bid to prolong life.

Not to be outdone in this literary war of words, Liu's commentary was followed by another from Japan's ambassador to the United Kingdom, Keiichi Hayashi:

"There are two paths open to China. One is to seek dialogue, and abide by the rule of law. The other is to play the role of Voldemort in the region by letting loose the evil of an arms race and escalation of tensions," he wrote in the same paper

The riposte prompted Chinese state media to warn "a war of public opinion between China and Japan is now in full swing."

"There are no flying cannonballs in the battlefield of public opinion, but it still requires the unity of the entire Chinese society to fight this war," The Global Times, a tabloid owned by the Chinese Communist Party mouthpiece The People's Daily, said on its website on Tuesday.

However, Internet users in both countries seemed amused rather than alarmed by the latest and surreal twist in the long-running diplomatic tit-for-tat.

"I think China and Japan are more like two kids who have not grown up," posted @Xiaowei Huang on China's popular Twitter-like platform Weibo.

"The method is refreshing and the cultural reference down to earth," said another Weibo user with the handle @luotiehang.

In Japan, Twitter user @emtyusuke welcomed the debate: "It is good to use wit and rhetoric to appeal each other's claim, without being overly emotional."

Abe's visit to the Yasukuni Shrine exacerbated tensions at a time when relations between Japan and China have been strained over the sovereignty of a set of islands in the East China Sea known as the Diaoyu islands in China and the Senkakus in Japan.

