The US has deployed a nuclear submarine with guided missiles after North Korea conducted missile tests.

The Americans sent their nuclear-powered sub, USS Michigan — one of the biggest submarines in the world capable of carrying about 150 Tomahawk missiles with a range of about 1,550 miles — to South Korea, for the first time in six years.

The sub arrived at the southeastern port city of Busan, but it is unclear how long it would stay in South Korean waters.

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This was done in response to the actions of North Korea, which resumed missile tests in protest of the US-South Korean live-fire drills.

This move by the US is part of a recent bilateral agreement on enhancing “regular visibility” of US strategic assets to the Korean Peninsula.

According to a statement by the South Korean Defence Ministry, the American and South Korean navies are to conduct drills on boosting their special operation capabilities and joint ability to cope with growing North Korean nuclear threats.

North Korea has argued it was forced to ramp up testing activities to deal with its rivals’ expanded military drills that it views as an invasion rehearsal, but experts say the North ultimately aims to modernise its arsenal and increase its leverage in eventual diplomacy.

On Thursday (June 15), North Korea fired two short-range ballistic missiles off its east coast, shortly after it vowed responses to the just-ended South Korea-US firing drills near the heavily armed border between the two countries.

These were the North’s first weapons launches since it tried to put its first spy satellite into orbit in late May, which failed miserably as the rocket carrying the spy satellite crashed into the waters off the Peninsula’s west coast.

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