In a state “guest house” on the outskirts of Pyongyang, Laura Ling and Euna Lee have been held for more than a month: valuable pawns in an growing international nuclear stand-off.

Hanging over the heads of the American journalists is the possibility of a show trial and ten years in a notoriously harsh North Korean prison camp. The outside world knows little about how they are holding up — because North Korea is not saying and the United States, while trying to free them through diplomacy, has tried to impose a blanket of silence.

The signs, though, are not good for the employees of Current TV, a web-based television channel founded by Al Gore, the former US Vice-President, because their future appears bound up in the widening rift between Pyongyang and much of the rest of the world over its recent missile launch. The reclusive regime of Kim Jong Il has halted all talks and expelled international experts monitoring its nuclear activities after the United Nations condemned its decision to fire a rocket over Japan.

Ms Ling, 32, a Chinese-American, has reported on drug wars in Mexico and native tribes in Brazil and is the younger sister of Lisa Ling, an award-winning TV journalist. Her father, Doug Ling, told reporters that he brought up his daughters as a single father and that both of them were sometimes “too adventurous” in covering news around the world. “I worry quite a bit. But I’m not losing any sleep over it,” he said. “Because I’m more or less used to it.”

Euna Lee, a Korean-American videographer, joined Current TV in 2005 after attending the prestigious Academy of Art University in San Francisco. The pair were accompanied on their trip to the region by a cameraman and an executive producer, both of whom managed to avoid capture.

The team, hoping to interview defectors from North Korea, began with a series of meetings in Seoul before flying to the Chinese city of Yanji, on the North Korean border. They were warned not to leave Chinese soil but ventured across the frozen Tumen river anyway. Exact details of their capture vary, with some accounts indicating that they were arrested by North Korean troops after refusing to stop filming, and others suggesting that they were pursued across the ice and back on to Chinese soil before being taken into custody.

Either way, within 24 hours Ms Ling and Ms Lee were taken in separate vehicles to Pyongyang for questioning. A week later it was announced that they would be put on trial.

Conviction for illegal entry carries up to three years in prison; the more serious crimes of espionage or “hostility toward North Korean people” are punishable by five to ten years.

The US State Department has said that it is making every diplomatic effort to free the two women and Mr Gore is said to have contacted Hillary Clinton, the Secretary of State, to ask for her assistance. The US has no embassy in North Korea but a representative of the Swedish Embassy in Pyongyang is said to have seen the journalists at the end of last month.

Koh Yu Hwan, a professor at Dongguk University in Seoul, said that Pyongyang was unlikely to release the journalists soon. Having two Americans was like having a “piece of rice cake rolling in for free”, he said.

“They’re going to make maximum use of this for multiple purposes. Rather than a trial by a criminal code, it will be a political trial.”

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