US and South Korea agree key nuclear weapons deal

To confront the nuclear threat from North Korea, the US and South Korea have struck a historic agreement.

Washington has consented to send US nuclear-armed submarines to South Korea on a regular basis and to include Seoul in nuclear planning activities.

South Korea has committed to refrain from creating its own nuclear weapons in exchange.

According to US President Joe Biden, the Washington Declaration will improve the allies' cooperation in preventing a North Korean assault.

Concern over North Korea's nuclear danger has grown on both sides of the conflict. Pyongyang is perfecting its long-range weapons, which can reach the US mainland, and creating tactical nuclear weapons that can hit South Korea.

The US has already agreed to use nuclear weapons to defend South Korea in accordance with a treaty.

However, on Wednesday Mr Biden said: "A nuclear attack by North Korea against the United States or its allies and partners is unacceptable and will result in the end of whatever regime were to take such an action."

In return, the US has demanded that South Korea remain a non-nuclear state and a faithful advocate of the non-proliferation of nuclear weapons. The US sees dissuading South Korea from going nuclear as essential, fearful that if it fails, other countries may follow in its footsteps.

But these US commitments are unlikely to fully satisfy the influential, and increasingly vocal, group of academics, scientists and members of South Korea's ruling party who have been pushing for Seoul to arm itself.

Dr Cheong Seong-chang, a leading proponent of South Korea going nuclear, said that while the declaration had many positive aspects, it was "extremely regrettable that South Korea had openly given up its right to withdraw from the Nuclear Non-Proliferation Treaty [NPT]", adding that this had "further strengthened our nuclear shackles".

President Biden said the US was continuing efforts to get North Korea back to the negotiating table. Washington says Pyongyang has ignored numerous requests to talk without preconditions.

The US hopes to convince North Korea to give up its nuclear weapons, but last year the North Korean leader Kim Jong Un declared the country's nuclear status "irreversible".

Some experts say it now makes more sense to discuss arms control rather than denuclearisation.