North Korean leader Kim Jong Un was pictured Monday showing off a new, smaller nuclear warhead — as he vowed to increase the production of weapons-grade material to expand his nuclear arsenal. 

Kim inspected the tactical warheads — called Hwasan-31s — during a visit to the Nuclear Weapons Institute, state-run Korean Central News Agency reported on Tuesday. 

The visit to the institute came at the conclusion of joint naval exercises between South Korea and the United States, intended to strengthen defense and response capabilities.

North Korea has long viewed such military drills as a rehearsal for an invasion.

The outlet said Kim pressed scientists during Monday’s visit to “expand in a far-sighted way” the production of nuclear fuel to meet goals of expanding the nuclear arsenal “exponentially.”

He also issued unspecified “important tasks” for the institute and the country’s nuclear sector. 

Kim went on to tell them they should “never be satisfied” with the country’s ability to counterattack with nuclear weapons, pointing out that “if the powerful and superior nuclear force going beyond imagination” is ready, no one would dare provoke North Korea, KCNA reported.

It also released images of Kim talking to officials at the institute, reviewing the array of tactical warheads, and examining plans and written orders for counterattack operations. 

Experts said the images show that North Korea is progressing in its goal of making smaller warheads that can be fitted on intercontinental ballistic missiles as well as on other delivery systems like submarines. 

“Those are not limited to tactical missiles but appear to be a miniaturized, lightweight and standardized warhead that can mount on various vehicles,” Kim Dong-yup, a South Korean naval officer who teaches at Kyungnam University, told Reuters.

“Now that the delivery vehicles are nearly ready, they would churn out warheads to secure second strike capabilities — perhaps hundreds, not dozens — while running centrifuges even harder to get weapons-grade nuclear material,” he said.​

Kim’s visit also coincides with a rash of launches by North Korea this month, including the testing of a “nuclear underwater attack drone” with the ability to target naval strike groups and enemy ports. 

​With Post wires​