Seoul, Oct 5 (IANS): The US and North Korea were set to resume working-level nuclear talks in Sweden on Saturday, after their preliminary meeting the previous day.

The talks will mark their first formal negotiation since February's summit between US President Donald Trump and North Korean leader Kim Jong-un in Hanoi that ended without a deal due to differences over the scope of Pyongyang's denuclearization and Washington's compensation, Yonhap News Agency reported.

The countries' deputy delegation chiefs -- Mark Lambert of the US and Kwon Jong-gun of the North -- were said to have had preliminary contact in Villa Elfvik Strand in Lidingo, northeast of Stockholm, on Friday to discuss the schedule and administrative issues for the formal resumption of their negotiations.

The pre-negotiation session was said to be "amicable and productive".

US Special Representative for North Korea Stephen Biegun and his North Korean counterpart, Kim Myong-gil, will lead Saturday's talks where they are expected to exchange their basic positions ahead of what could be another grueling tug of war.

Their negotiations will centre on how to make substantive progress in the implementation of the landmark agreement that Trump and Kim reached during their first summit in Singapore in June 2018.

The agreement includes a set of their commitments to build new bilateral relations, make joint efforts to build a lasting and stable peace regime on the Korean Peninsula and work towards its "complete denuclearization".

Before the negotiations, the North's delegation chief Myong-gil said he bore "high expectations and optimism", Yonhap reported.

In recent weeks, top US officials' statements have also raised optimism about a compromise with Pyongyang.

Trump has made remarks that hinted he is warming to Pyongyang's call for a "new calculation method," while Secretary of State Mike Pompeo has repeated conciliatory messages, such as there being a "bright future" for a nuclear-free North Korea.