The families of the two US journalists sentenced to 12 years' hard labour in Noth Korea have apologised to the regime on the women's behalf and begged Pyongyang for "compassion".

In their first public remarks since Laura Ling and Euna Lee were convicted of an illegal border crossing and unspecified "grave crime", the families said in a joint statement that they were shocked and devastated by the sentences and expressed concerned for the women's mental state and well-being.

The statement came as Hillary Clinton, the US Secretary of State, called on North Korea to show clemency and deport the women, who were arrested on the country's border with China on March 17.

The pair, who worked for the internet-based Current TV, were picked up as they reported on the plight of refugees attempting to flee the repression in North Korea over the notoriously porous border with China.

Their families said that they apologised if the reporters had accidentally strayed across the border, and repeated Mrs Clinton's call for clemency.

"We ask the Government of North Korea to show compassion and grant Laura and Euna clemency and allow them to return home to their families," they said.

Ms Ling, 32, suffered from an ulcer, and Ms Lee's four year-old daughter "is displaying signs of anguish over the absence of her mother," the statement said.

"We believe that the three months they have already spent under arrest with little communication with their families is long enough."

During their 12 weeks' incarceration, the women have been allowed to make only one telephone call each to their parents, and have received only three visits, from the Swedish Amassador to Pyongyang who represents US interestes in the absence of formal diplomatic relations.

“Though the girls are strong, we know that they are very, very scared,” their families said recently.

Ms Ling and Ms Lee were sentenced after a five-day trial held in secret at Pyongyang Central Court, the highest court in the country, from which there is no appeal.

The sentence exceeded the maximum ten years that had been expected, although there was relief in pollitical circles that the journalists had not been charged with espionage, indicating that North Korea might have seen their cases as being separate from Pyongyang's political tensions with Washington.

The women had been accompanied by a Chinese guide and an American cameraman, Mitch Koss, who also worked for Current TV, founded by Al Gore, the former US Vice-President.

Mr Koss returned to America after his colleagues' arrest. He has not said whether they crossed the frozen river that marks the frontier, or were lured or abducted to the North Korean side

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