SEOUL, April 25 (Xinhua) -- A U.S. nuclear-powered submarine on Tuesday arrived at the southern port of Busan, South Korea, amid tensions on the Korean Peninsula, YTN television reported.

The USS Michigan guided-missile submarine has already arrived at Busan, the South Korean military was quoted as saying. The broadcaster did not elaborate on the exact time of its arrival.

Although the nuclear submarine is not supposed to participate in any drills or military operations, its call would send a meaningful message to the Democratic People's Republic of Korea (DPRK), said the YTN.

At a national meeting held Monday, the DPRK again warned the United States that it would stage preemptive nuclear strikes against American forces.

The USS Michigan is one of four Ohio-class ballistic missile submarines loaded with nuclear missiles. The 170-meter-long, 18,000-ton submarine can carry as many as 150 Tomahawk cruise missiles with a range of some 1,600 km.

The Michigan's call on South Korea came amid mounting tensions on the peninsula. The USS Carl Vinson nuclear-powered aircraft carrier is sailing toward the peninsula.

The rare re-routing of the super-carrier to the peninsula had raised concerns about possible airstrikes on the DPRK's nuclear facilities.

Meanwhile, the DPRK Foreign Ministry said in a statement Tuesday that the Korean Peninsula is on the verge of war due to "reckless action" by the United States using both economic sanctions and increasing military threats.

According to South Korea's military, the DPRK conducted large-scale live-fire artillery exercises on Tuesday to mark its army anniversary.

The DPRK's artillery drills came amid ongoing joint military exercises of South Korea and the United States.

The U.S.-South Korea joint war games, which were denounced by the DPRK as a rehearsal for northward invasion, would last till the end of this month.