South and North Korea agreed Friday to allow South Korean firms to gradually establish full operations in an industrial complex being built in the North Korean border city of Gaesong beginning next year.

The two sides also agreed to complete building a 33,000-square-meter facility that will serve as a demonstration complex in the first half of this year and immediately thereafter allow South Korean firms to move in.

The accord was one of the seven points in a joint statement released Friday at the end of four-day talks in Seoul to review the progress of ongoing joint economic projects, including the industrial park and cross-border transportation links.

On the reconnection of inter-Korean railways and roads, the two Koreas agreed to launch trial train services within the year and finish the pavement of roads at the earliest date possible.

South and North Korea agreed to convene in Pyongyang in June to hold another round of economic cooperation talks.

The North's delegation departed for Pyongyang on Friday.