North Korean leader Kim Jong Un was at the centre of a massive parade and rally on Saturday to mark the 75th anniversary of the country's ruling party.
The army exhibited a new intercontinental ballistic missile with a larger wingspan during the event, as many analysts had expected.
State television showed pictures of Kim appearing at midnight in a grey suit and tie as he was greeted by cheering crowds in the capital Pyongyang.
It is unusual for North Korea to hold parades so late at night, though observers said the hours of darkness may have helped protect sensitive information about the weapons that were being rolled out.
Saturday's parade saw other military hardware and vast columns of people march past the senior leadership.
But Kim did not directly criticise the United States in his speech, choosing instead to focus on a domestic message by urging his people to remain firm in the face of the coronavirus pandemic.
He said the North’s continuing efforts to develop its nuclear deterrent was necessary for the country's defence and that it did not target any specific country.
But he added: "if any force harms the safety of our nation, we will fully mobilise the strongest offensive might in a pre-emptive manner to punish them."
The new missile that was paraded was larger that the Hwasong-15, the longest-range projectile that the regime has tested so far, the EFE agency reported.
No name was announced for the projectile and it did not appear to have yet been tested.
North Korea has not launched an intercontinental ballistic missile since the Hwasong-15 in November 2017. It is theoretically capable of reaching the United States.
North Korea's ruling Workers' Party traces its roots back to October 10, 1945, and fireworks marking the anniversary were also on display.