This picture released on Sunday by North Korea's official Korean Central News Agency (KCNA) shows North Korean leader Kim Jong-un (center) celebrating the test-firing of a newly developed multiple rocket launcher at an undisclosed location. Photo: AFP

North Korea on Monday demanded the US provide ­security guarantees as a precondition to resuming deadlocked nuclear talks, dampening hopes for progress at a working-level dialogue expected in the coming weeks.

Negotiations between Pyongyang and Washington have been gridlocked since a second summit between the North's leader Kim Jong-un and US President Donald Trump in February ended without a deal.

The pair agreed to restart working-level dialogue during an impromptu meeting at the Demilitarized Zone dividing the two Koreas in June, and Pyongyang last week offered to hold those talks in late September, a move the US said was "encouraging."

But hours later, Pyongyang carried out the latest in a series of weapons tests.

A senior official from the North's foreign ministry said Monday that "discussion of denuclearization may be possible when threats and hurdles endangering our system security and obstructing our development are clearly removed beyond all doubt."

North Korea has always insisted that security guarantees would be necessary as part of any deal - but it has not generally demanded them as a precursor to negotiations.

The director-general of the department of US affairs, who was not named, said in a statement carried by the official Korean Central News Agency that working-level talks were expected to be held "in a few weeks."

The North Korean leader asked Trump to visit Pyongyang in a letter sent last month, South Korea's JoongAng Ilbo newspaper reported Monday.