The announcement by Kim Dae-jung comes after North Korea renewed its commitment this week to resume nuclear disarmament talks, while at the same time vowing to strengthen its stockpile of atomic weapons to counter what it called extreme US hostility.
In October, Washington imposed sanctions on eight North Korean companies it said were fronts for proliferating weapons of mass destruction but has repeatedly said it has no intention to invade the North.
Kim won the Nobel Peace Prize after he set up an unprecedented meeting with Kim Jong-il, the leader of North Korea, six years ago. It resulted in roads and railways being rebuilt through the fortified demilitarised zone border that has split the peninsula since the 1950-53 Korean war.
A South Korean government official said Kim Jong-il had twice invited Kim Dae-jung to visit the North and confirmed that Seoul and Pyongyang were in talks about the logistics and timimg of a possible visit.
The meeting in 2000 was seen as a significant step towards reducing tensions between the two states.
Kim has told South Korean media he would like to see the rail links restored soon. South Korea has also been pressing the North to finish the work on its side of the border and to allow test trains to run through the frontier.
South Korea has built new stations and is constructing a customs house near a border railway station.
Kim Dae-jung was initially hailed as a hero for organising the summit, but was later embroiled in a scandal over about $500 million said to have been funnelled to the North to secure the meeting with Kim Jong-il.
Some of Kim Dae-jung's senior aides were convicted of making illegal payments, although the former president avoided any legal blame.