Updated

South Korea on Sunday warned the North it was "reaching the limit" of its patience over stalled talks to revive a joint industrial complex once seen as a rare symbol of cooperation between the rivals.

Six rounds of cross-border meetings aimed at restarting the venture, a key source of hard currency for the North Korea's communist regime, produced little progress as each side squabbled over who would take responsibility for the shutdown.

South Korea proposed "final" talks on the Kaesong industrial zone, which has remained shuttered since early April following military tensions, on July 28.

The most recent meeting on July 25 ended in acrimony with no date set for the next talks and Pyongyang officials accusing Seoul counterparts of being "arrogant".

Seoul's unification ministry, which handles cross-border affairs, issued Sunday another call for the North to show "responsible words and actions, instead of silence".

"The North should bear in mind that South Koreans...are reaching the limit of their patience," the ministry spokesman Kim Hyung-Seok told reporters.

"If it truly believes that the Kaesong complex is the touchstone of inter-Korea relations...it should demonstrate it with responsible words and actions instead of silence," he said.

The zone -- built just north of border in 2004 -- had survived previous inter-Korea crises but eventually fell victim to two months of elevated tensions following a nuclear test by the North in February.

Pyongyang, taking issue with military tension on the peninsula and Seoul's joint army exercises with the US, withdrew all 53,000 workers who produced textiles and other goods at factories for some 120 South Korean firms.

Seoul insists that Pyongyang provides a binding guarantee that it would not close the complex again in the future and partially covers damages for the affected firms, estimated to be nearly one billion dollars in total.

Pyongyang has rejected the demand, arguing that ultimate responsibility for Kaesong's closure lay with the South.

Kaesong-based businessmen pleaded last week with Seoul to show more "flexibility" in negotiations with Pyongyang so that they could resume operations as soon as possible.