Seoul, Feb 24 (IANS): South Korea on Saturday welcomed fresh unilateral sanctions described as the heaviest ever adopted by the US against North Korea, and said the measures would contribute towards the common goal of the denuclearisation of Pyongyang in a peaceful manner.

The US Treasury Department on Friday imposed the new economic sanctions on 27 companies and 28 vessels located or registered in numerous countries, trading with North Korea, reports Efe news.

"(The sanctions) were a reaffirmation of the US side's will to move towards a peaceful, diplomatic resolution to the North Korean nuclear issue," a South Korean Foreign Ministry spokesperson told Yonhap news agency.

Seoul considers the measures to be a part of the efforts "to set the North onto a path towards denuclearization" and expressed the hope of continuing its cooperation at all levels with the US in order to resolve the North Korean issue in a peaceful manner.

US President Donald Trump said on Friday that if the new sanctions on North Korea "don't work, we'll have to go phase two", which he said could be "a very rough thing".

The latest sanctions from Washington come at a moment of thaw in inter-Korean relations owing to the Winter Olympics, currently under way in South Korea's PyeongChang county.

The sanctions coincide with a trip to South Korea by the US president's daughter and advisor Ivanka Trump to attend the closing ceremony of the Winter Olympics on Sunday, which will also be attended by a high-level delegation from Pyongyang.