Carter last visited North Korea in August 2010 to secure the release of imprisoned American Aijalon Gomes [EPA]
Jimmy Carter, the former US president, has arrived in Pyongyang hoping to meet North Korea's leader as part of a mission to discuss dangerous food shortages and stalled nuclear disarmament talks.
Carter was joined by Martti Ahtisaari, former Finnish president, Gro Brundtland, former Norwegian prime minister and Mary Robinson, former Irish president, for the three-day visit to North Korea, which started on Tuesday.
The former leaders were not told ahead of their trip who they would meet, but said they hoped to see Kim Jong Il, the North Korean leader, and his son and heir apparent Kim Jong Un.
The mission comes as diplomats struggle to find a way to restart talks meant to persuade the North to abandon its atomic weapons ambitions.
Dismal ties between North and South Korea, which have ruined efforts to restart the nuclear talks, will also likely be on the agenda. Animosity has soared between the neighbours since the North allegedly torpedoed a South Korean warship in March 2010.
Pyongyang shelled a South Korean island in November, killing two civilians and two marines.
South Korea is demanding an apology for both incidents before allowing deeper talks, but North Korea says it was not responsible for the sinking of the warship.
Period of tension
Before flying from Beijing to Pyongyang, Carter told South Korea's Yonhap news agency that he did not intend to raise the case of Korean-American Jun Young Su, who is being held in North Korea, reportedly on charges of carrying out missionary activity.
The US state department said last month that Carter would not be carrying any official messages.
While in the country, Carter and his fellow former world leaders also plan to discuss food shortages that could threaten many North Koreans.
Years of poor harvests, a lack of investment in agriculture and political isolation have left the North severely vulnerable to starvation.
The average amount of food distributed by the government to each person has dropped this year from 1,400 calories per day to just 700, according the UN's World Food Program.
Former Irish president Robinson said a recent UN study based on conditions throughout North Korea classified 3.5 million out of the country's 24 million people as "very vulnerable" to starvation.
She also expressed concern that conditions stood to worsen with cuts in food distribution.
Stalled nuclear negotiations
The world leaders' trip comes amid efforts on several fronts to reinvigorate stalled six-nation nuclear negotiations.
China's top nuclear envoy was due in Seoul on Tuesday for talks, while a South Korean delegation was to meet US diplomats in Washington.
Meanwhile, North Korea's top nuclear envoy reportedly travelled to Beijing earlier this month to discuss restarting the talks, which involve the two Koreas, the United States, China, Japan and Russia.
In 1994, Carter travelled to North Korea during another period of high tension over the North's nuclear programme. He met then-leader Kim Il Sung, Kim Jong Il's father and the North's founder, and helped to broker a US-North Korea nuclear deal.
He last visited North Korea in August to secure the release of imprisoned American Aijalon Gomes, who had been sentenced to eight years of hard labour for crossing into the North from China.
Carter did not meet Kim then because the leader was on a rare visit to China, his nation's biggest ally and aid provider.