Seoul, Aug 22 (IANS): South Korea and the United States will continue efforts to enhance practical capabilities and readiness to respond to "any type" of North Korean nuclear threats, Seoul's foreign ministry said on Thursday.

The ministry made the statement after a media report suggested that US President Joe Biden approved a secret strategy in March to focus on China's growing nuclear threats and prepare his country for possible coordinated nuclear challenges from North Korea, China and Russia.

The highly confidential Nuclear Employment Guidance, updated around every four years, was only distributed to a handful of security officials and Pentagon commanders, reports Yonhap news agency, quoting The New York Times.

When asked to comment with regard to the news report, a foreign ministry official in Seoul said the allies are continuing to enhance the effectiveness of extended deterrence, citing the Nuclear Consultative Group (NCG) in response to the North's advancing nuclear and missile threats.

"Going forward, the US and South Korea will continue to develop practical capabilities and readiness to effectively deter and respond to any type of North Korean nuclear threats," the official said on condition of anonymity, without elaborating further.

The NCG was launched last year to strengthen the US commitment to using the full range of its capabilities, including nuclear, to defend its ally.

As part of the NCG efforts, the defence officials of the two sides signed a set of nuclear deterrence guidelines in July, but questions have lingered over what the guidelines entail as the details have been kept undisclosed.