South Korea unveils most powerful missile which could reach North Korea underground bunkers

South Korea has unveiled its most powerful ballistic missile and other weapons targeting North Korea during a massive Armed Forces Day ceremony, as the South's president warned that the North's regime would collapse if it attempted to use nuclear weapons.

South Korea's weapons displays and warning against North Korea on Tuesday came after its northern rival recently rose regional animosities by disclosing its uranium-enrichment facility and tested missiles ahead of the US presidential election in November.

"If North Korea attempts to use nuclear weapons, it will face the resolute and overwhelming response of our military and the (South Korea)-US alliance," President Yoon Suk Yeol told thousands of troops gathered at a military airport near Seoul. "That day will be the end of the North Korean regime."

"The North Korean regime must abandon the delusion that nuclear weapons will protect them," Yoon said.

During the ceremony, the South Korean military displayed about 340 military equipment and weapons systems. Among them was its most powerful Hyunmoo-5 ballistic missile, which observers say is capable of carrying about eight tons (7,257kg) of a conventional warhead that can penetrate deep into the earth and destroy underground bunkers in North Korea. It was the first time for South Korea to disclose that missile.

The US flew a long-range B-1B bomber during the ceremony in an apparent demonstration of its security commitment to its Asian ally. South Korea also flew some of its most advanced fighter jets.

Later on Tuesday, South Korea will parade its troops and weapons through the streets of Seoul, the capital, as part of efforts to boost military morale and demonstrate its deterrence capabilities against potential North Korean