North Korean leader Kim Jong Un said the country is now implementing a nuclear force construction policy to increase the number of nuclear weapons “exponentially,” state media KCNA said on Tuesday.

Kim gave a speech on North Korea’s founding anniversary on Monday, KCNA said.

North Korea must more thoroughly prepare its “nuclear capability and its readiness to use it properly at any given time in ensuring the security rights of the state,” Kim said, according to KCNA.

A strong military presence is needed to face “the various threats posed by the United States and its followers,” Kim added.