The United States' diplomatic approach to North Korea has not changed despite the nations' missile test launches last week, but the United States is ready in the event diplomacy is not successful, Acting Defense Secretary Patrick Shanahan said in an interview airing Monday.

"The strategy with North Korea hasn't changed, the diplomatic one," Shanahan told Fox News' Brian Kilmeade for an interview airing on "Fox & Friends," while explaining the goal of full denuclearization still remains.

However, he added, "my job is to make sure that we are prepared in the event diplomacy fails. That's my focus with the military." He noted the United States has had no change to its posture, preparation, or readiness.

Shanahan, who President Donald Trump tagged last week as his nominee for the secretary slot, also during the interview denied critics who claim he has been moving from crisis to crisis without an overall vision.

"We have operations underway in over 160 countries," he said. "Because there are so many different dynamics, it's difficult to connect the dots when you are behind the curtain can you see that the dots connect. They don't always line up with the time frame you and I would like."

He also commented about the ongoing issues with Russia, which has become involved in crisis worldwide, including in Syria, Venezuela, and more.

"We need to address their aggression," Shanahan said. "Their priority has been their modernization of nuclear weapons. When we look at the types of weapons they're modernizing in violation treaties we have between our countries, these are things that need to be addressed."

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