The former US Army general dismissed the possibility of bringing North Korea back to the negotiating table, which he blamed on the US President Donald Trump.
He said: “The problem is we’ve got so many crises going on now, potentially, that he’s overloading the diplomatic effort, as well as the US armed forces’ ability to deal with it.
“I don’t want us to take our eye off North Korea.
“The current language out of the administration, that lack of a diplomatic and serious engagement strategy, in my view, has us sliding toward war by next summer.
“This war is on schedule under this administration.”
MSNBC news anchor Brian Williams noted that General McCaffrey does not have a reputation for inflammatory rhetoric, which makes his warning even more chilling.
Mr Williams said: “I’ve known the general for many years. I know him as a level-headed man not given to hyperbole.”
Last night, North Korea also revealed that the state would target Australia if the country continued to align themselves with the US.
Pyongyang’s Korean Central News Agency (KCNA) warned that Australia was “showing dangerous moves of zealously joining the frenzied political and military provocations of the US”.
Earlier this week, experts revealed concerns that North Korea would “retaliate” with a ballistic missile ahead of an upcoming joint naval drill by the US and South Korea.
Satellite pictures have reportedly shown missiles mounted on launchers being transported out of hangars near Pyongyang.
US and South Korean officials suspect the North Korean dictator is planning to launch missiles capable of reaching US territory.