Sigmar Gabriel said any war involving the secretive dictatorship would be “devastating”.
“A war on the Korean Peninsula will be devastating. In the worst-case scenario, it could result in more victims than World War II,” Gabriel told local newspaper Aachener Zeitung on Thursday via a translation by Tass news agency.
Gabriel added that North Korean despot Kim Jong-Un “is threatening the entire region by holding his finger on the red button.”
The prospect of conflict has become terrifyingly real as North Korea continues high-stakes missile tests, while US President Donald Trump ramps up his rhetoric over the issue.
A launch on Tuesday saw a North Korean rocket fly over the north of Japan, prompting warnings to citizens to “take cover”.
A statement attributed to Jong-Un described that test as a trial for a possible offensive against the US Pacific territory of Guam.
But it puzzled experts as to its true purpose. The North has long been testing medium and long-range ballistic missiles capable, in theory, of carrying nuclear warheads.
Trump responded in a furious tweet, saying US diplomacy with the dictatorship was fruitless. “Talking is not the answer,” he wrote.
Asked by reporters this week for his response to the latest missile test, Trump said ominously: “We’ll see.”
Trump previously warned North Korea it faced “fire and fury” if it continued to escalate its military threats.
It came after The Washington Post published extracts from a Defence Intelligence Agency report which said North Korea was successfully producing nuclear missiles.
Nearly 60 million people lost their lives in the Second World War, which raged between 1939 and 1945. That was around three percent of the entire global populace at the time.