SEOUL, South Korea (CNN) -- South Korea declined a request by North Korean leader Kim Jong Il for South Korean President Roh Moo-hyun to extend the summit one day, according to South Korean reporters covering the summit in Pyongyang. No explanation of the decision was immediately given.
Extended afternoon talks between the two leaders had delayed some events, prompting the invitation for Roh.
According to the South Korean press corps, Kim said, "How about returning to Seoul on Friday after having a leisurely lunch tomorrow and do the things originally planned for this afternoon?"
The summit is scheduled to end Thursday morning, when the leaders are expected to issue a joint statement. Roh will return to Seoul afterward.
The request was made after the two leaders opened formal talks Wednesday at the first summit between the split nations in seven years.
Roh and Kim held morning meetings before breaking for lunch and then resumed discussions in an afternoon session.
Hundreds of North Koreans cheered Roh's arrival at the April 25 Hall of Culture in downtown Pyongyang on Tuesday, waving large spikes of KimJongIlia, the brilliant pink flower named for their reclusive leader.
The two leaders shook hands and reviewed the North Korean military during a short opening ceremony. Later, Roh attended a welcoming dinner hosted by North Korea's second-most senior leader, Kim Yong Nam, president of the Presidium of the Supreme People's Assembly. Kim Jong Il did not attend.
"Peaceful co-existence and co-prosperity of the two Koreas depend on our willingness and efforts," Roh said at the dinner. "Depending on our efforts, the two Koreas will be able to play a leading role in the creation of a new order of integration in Northeast Asia." Watch what can be expected on day two of the summit »
"Inter-Korean relations should be further developed to pave the way for national unification," said Roh's host, Kim Yong Nam. "It's our sacred task."
On Tuesday Roh became the first South Korean leader to walk across the heavily fortified Demilitarized Zone between the two countries. His predecessor, Kim Dae-jung, flew to Pyongyang for the first Korean leaders summit in 2000.
"As president, I'm crossing this forbidden line this time," Roh said. "After I'm back, I hope that more people will follow suit, and then this forbidden line will eventually be erased."
The meeting with Kim Jong Il, announced in early August, was initially scheduled for the end of that month but was postponed after massive flooding in Pyongyang.
The summit coincides with six-party talks in China's capital, Beijing, on North Korea's nuclear-weapons program, which Pyongyang has vowed to disable by the end of the year.
The Koreas summit also comes in the final months of Roh's scandal-ridden term. Some analysts suspect he is hoping the Pyongyang meeting will boost his sagging approval ratings and help position his party in the upcoming elections against the conservative opposition.
A joint statement following the 2000 summit indicated that the next meeting between the Korean leaders would take place in Seoul.
Roh's decision not to push for a meeting outside the North Korean capital was criticized by Bruce Klinger of the Heritage Foundation's Asian Studies Center in a recent article titled "Seoul's Impetuous Summit Initiative."
"It is indicative of Roh's eagerness that he failed to insist on holding the summit in the Kaesong special economic zone in North Korea to highlight the flagship initiative of Seoul's engagement policy," Klinger wrote.
But one South Korean woman told CNN she believes the summit "is our last chance" to negotiate the freedom of hundreds of Korean prisoners of war and abductees. Her father was a fisherman on a boat believed abducted by the North more than 30 years ago.
"The abductees and POWs are aging, so within five years they might be dead," Choi Sung-yong said.
Other South Koreans have protested the summit -- including one man who set himself on fire during a demonstration in Seoul -- demanding that Roh push North Korea on its human-rights violations during the talks.
Instead, the summit is expected to address military tensions, including a sea-border dispute on the west coast of the Korean peninsula, and economic issues, such as how South Korean businesses can help the North climb out of extreme poverty.
The 2000 summit, part of Kim Dae-jung's policy of engagement with North Korea, paved the way for his Nobel Peace Prize awarded that same year.
But South Korean investigators later revealed that Kim Dae-jung paid hundreds of millions of dollars to secure the meeting, the first between Stalinist North Korea and capitalist South Korea.
In his August 22 article, Klinger wrote that "it is unlikely" Seoul made any secret cash payments for this week's meeting but noted that "Kim Jong Il does not cooperate for free."
"The Roh Moo-hyun administration probably offered some inducement, such as new developmental aid or expansion of existing South-North economic projects," Klinger wrote. E-mail to a friend
CNN's Seoul Bureau Chief Sohn Jie-ae contributed to this report.