South Korea's rival political parties agreed Monday to present a unified response to North Korea's call last week for joint parliamentary talks on a non-aggression pact.

Representatives of the south's four political parties met at the National Assembly and agreed to send by Aug. 1 a letter responding to the call.Party officials said the groups would continue talks this week to solve minor differences over details such as the agenda and the site for the talks.

"There were no striking differences, although no agreement was reached," said an aide to National Assembly Speaker Kim Jai-soon, who presided over today's meeting.