Rows of the intercontinental ballistic missiles known as KN-08, which some think could fly far enough to reach the continental US, were paraded through the capital as part of a massive military parade marking the 70th anniversary of the ruling Workers Party.

A defence analyst in Seoul said the new missile appeared to have been modified to allow it to be fitted with a miniature nuclear warhead -- a claim echoed by North Korea's state TV -- but others experts said it was impossible to tell.

North Korea has long claimed it has technology capable of launching nuclear bombs at its distant enemies, but experts are sceptical whether the impoverished country has acquired the sophisticated technology needed to produce such weapons.

"With the vengeful desire to turn the citadel of our enemies into a sea of fire, our powerful tactical rockets loaded with diversified and miniaturised nuclear warheads are on the move," the commentator said, as rows of missiles were shown on screen.

Leader Kim Jong-Un on Saturday told crowds assembled for the parade that the country's armed forces "are capable of fighting any kind of war provoked by the US and we are ready to protect our people and the blue sky of our motherland".