Seoul, South Korea - South Korea - North Korea said on Wednesday that leader Kim Jong-un observed the first missile tests of the recently launched destroyers, the first such warship in the north, and called for accelerated efforts to improve his naval nuclear attack capabilities.

North Korea unveiled the 5,000-ton destroyer last week, equipped with what it calls the most powerful weapon in the warship industry. At a ceremony at Nampo Port on Friday, Kim Jong Il said the ship's construction "breakthrough" in the modern North Korean navy.

Outsider experts say this is North Korea's first destroyer and it is likely built with the assistance of Russia. They say North Korea's naval forces lag behind South Korea's navy, but still see destroyers as a serious security threat because it can enhance North Korea's attack and defense capabilities.

South Korea's official Central News Agency said on Wednesday that Kim Ben watched tests of the destroyer's supersonic and strategic cruise missiles, air defense missiles, automatic guns and electronic support guns earlier this week.

The report said he appreciated the ship's powerful strike weapons and conventional defenses and set up a mission to speed up nuclear weapons for the Navy's nuclear weapons.

Kim Jong Il said at a ceremony on the ship that the destroyer will be deployed early next year. He said the acquisition of nuclear-powered submarines would be his next important step in strengthening the navy. He stressed the need to strengthen North Korea's deterrence capabilities in response to what he called escalation of hostilities in the north.

Lee Illwoo, a South Korean defense network expert, said analysis of warship photos showed that its anti-aircraft radar system may have come from Russia. He said the engine system of the warship and some of its anti-air weapon systems may also come from Russia.

North Korea and Russia have been significantly expanding military and other cooperation in recent years, with the north providing troops and traditional weapons to support Russian war efforts against Ukraine. The United States, South Korea and its partners fear that Russia may return the supply of high-tech weapons technology to North Korea that could enhance its nuclear program as well as transport other military and economic assistance.

Lee said the deployment of warships using advanced radar systems near North Korea's west coast could greatly support its air defense capabilities for the capital Pyongyang. Lee said South Korea has 12 destroyers, still surpassing North Korea's navy. But he said that a North Korean destroyer could carry about 80 missiles, which could still pose a serious threat, as South Korea's navy is unlikely to prepare for such an enemy warship.

Hostility on the Korean Peninsula is rising as North Korea continues its weapons testing activities aimed at expanding its nuclear and missile arsenal. On Monday, North Korea confirmed for the first time that it had sent combat troops to Russia in support of its war against Ukraine. Russian President Vladimir Putin thanked North Korea and promised not to forget the sacrifices of North Korean soldiers for Russia.