Media reports say former US president Carter planning visit to North Korea

Former US president Jimmy Carter is reportedly planning another visit to North Korea following the jailing of American citizen Kenneth Bae for anti-government crimes, according to South Korean media. Mr Bae (44), a tour operator of Korean descent, was sentenced to 15 years’ hard labour this week after being arrested near the North’s border with China last November.

The conviction ups the ante in Pyongyang's two-month face-off with Washington, which began with the announcement of new United Nations sanctions in March and the start of US-South Korea war games on the divided Peninsula. Mr Bae has already spent months in an isolated cell, according to the Seoul-based Korea Herald and may now become a bargaining chip in Pyongyang's unique brand of white-knuckle diplomacy.

Five American citizens have been detained inside the North since 2009 and some have also been sentenced to long prison terms with hard labour. The best known are journalists Euna Lee and Laura Ling, charged with "hostile acts against the republic"in March 2009 and only freed after another former president, Bill Clinton, made a pilgrimage to meet now deceased leader Kim Jong-il.

Labour camps
Their arrests drew worldwide attention to the North's chain of labour camps, where an estimated 150,000 to 200,000 prisoners are detained, according to the US state department. Defectors say the gulags are often built near mines or logging camps and frequently work inmates to death. Many of the prisoners are children or the relatives of political outcasts.

The most vivid account of life inside the gulags comes from Shin Dong-hyuk, the only person known to have been born and raised in a camp, and to escape to tell his tale. In journalist Blaine Harden's recent book, Escape From Camp 14 , Mr Shin describes eating rats and insects to avoid starvation, and informing on his own mother and brother when he heard them planning to escape. He says he was forced to watch their executions.

As American citizens, however, Ms Lee and Ms Ling were treated well during their 140-day ordeal, though they rarely had enough to eat. They later described being watched by guards day and night but suffered none of the horrors suffered by Mr Shin. Unlike North Korean prisoners, the treatment of Americans is monitored. Swedish diplomatic envoys in the North have been in contact with Kenneth Bae for months, trying to secure his release.

Border city
Mr Bae was arrested after he crossed at the North's Korean border city of Rajin in November, while leading a group of five visitors. The area is trying to attract foreign investment and tourists, and is also a well-known base for Korean Christian activists sheltering refugees.

It is possible that Mr Bae, reportedly a devout Christian, was in contact with these groups.

Mr Carter is widely credited with pulling the North and the US back from the brink of war in 1994 when he visited Pyongyang and negotiated an energy deal with Kim Jong-il. In 2010, he won the release of American Aijalon Mahli Gomes, sentenced to eight years’ hard labour for illegally entering the North.

According to the South Korean Yonhap news agency, Mr Carter has told US secretary of state John Kerry he is returning to Pyongyang. “North Korea appears to have invited him,” said the agency, quoting an anonymous diplomatic source in Seoul.

The story was denied last night by Mr Carter’s spokeswoman. But the ex-president last month urged Washington to open a dialogue with Pyongyang and avoid war.