South Korean Foreign Minister Ban Ki-moon has criticised a recent visit by Japan's prime minister to the controversial Yasukuni war shrine.
Mr Ban described the atmosphere at the meeting as 'harsh'
During talks with his counterpart in Tokyo, Mr Ban said the "people of South Korea were disappointed" by Prime Minister Junichiro Koizumi's actions.
But he also urged Seoul and Tokyo to look to their future relationship.
Mr Ban's visit to Japan looks set to be dominated by the row over Mr Koizumi's latest shrine visit, on 17 October.
The shrine honours Japan's war dead, including 14 people judged as war criminals after World War II, and both South Korea and China have repeatedly condemned visits by senior Japanese politicians to the shrine.
In the immediate aftermath of Mr Koizumi's latest visit, Mr Ban said he would drop plans to visit Japan completely.
But on Wednesday he said that the trip was necessary.
"My visit this time was realised in a harsh atmosphere," Mr Ban acknowledged on Thursday.
"But I have come to discuss with you North Korean nuclear issues and make the Apec [Asia-Pacific Economic Co-operation] summit a success," he told Japan's Foreign Minister Nobutaka Machimura.
Built in 1869 to honour victims of the Boshin Civil War
Now venerates the souls of 2.5m of Japan's war dead
Those enshrined include 14 Class A war criminals
"Relations between South Korea and Japan must develop in a forward-looking way," Mr Ban added.
While Mr Ban's trip is going ahead, a meeting between Mr Koizumi and South Korean President Roh Moo-hyun is still in doubt.
Mr Ban told reporters earlier this week that his government would assess relations between the two sides before making a final decision.
But after meeting Mr Ban on Thursday, Mr Machimura told reporters that the prospect for a visit by Mr Roh looked "grim".
During the foreign ministers' meeting, the two men are believed to have discussed the possibility of creating a new war memorial to be used instead of the Yasukuni shrine.
Such a move could lessen tensions between Japanese who feel the need to remember their war dead and South Koreans and Chinese, who view visits to a shrine commemorating war criminals as offensive.
But a senior Japanese official told reporters that the issue of constructing a new war memorial was not a simple one.
"South Korea thinks a new war memorial would be a substitute for Yasukuni, but that may not necessarily be the case. These two are separate'' things, he told local media.
Mr Ban is expected to meet Mr Koizumi on Friday.