Panetta: North Korea 'most serious crisis' involving nukes since Cuba

Former Defense Secretary Leon Panetta warned of the gravity of the situation between the US and North Korea, saying, "we're dealing with probably the most serious crisis involving a potential nuclear war since the Cuban Missile Crisis."

Tensions between the United States and North Korea have been heightened this week as leaders from both countries have touted their military capabilities. On Friday, President Donald Trump sent a clear message to North Korean leader Kim Jong Un, stating that he "will truly regret it and he will regret it fast," if he carries out an attack on Guam or a US ally.

"If he utters one threat in the form of an overt threat ... or if he does anything with respect to Guam, or any place else that is an American territory or an America ally, he will truly regret it and he will regret it fast," Trump said while on his 17-day working vacation in New Jersey.

This statement was not dissimilar to his remarks earlier in the week following threats from North Korea that the county was preparing a plan to strike the US territory of Guam.

In an interview on CNN that aired Friday, Panetta told Wolf Blitzer the rhetoric is "simply fueling this situation."

The US is currently pursuing talks through diplomatic backchannels, however Panetta said he's is concerned about the possibility of a "miscalculation."

"There is a mistake by someone in North Korea or someone in South Korea or someone elsewhere that suddenly has us into a war on the Korean Peninsula," said Panetta, who served in former President Barack Obama's administration. "I really do think that what is required now is a lessening of this rhetoric and allow our actions to speak for the United States, not our words."

In addition to serving as secretary of defense, Panetta also was the CIA director and a former White House chief of staff.

"We need a president to speak in a steady and calm and stable and responsible way," Panetta said.