Washington - US Secretary of State Hillary Rodham Clinton Friday called on Pyongyang to release the two US journalists being tried in North Korea and said the US considers the trial a "step toward" their release.

She also expressed strong concern on behalf of the two women accused of entering the country illegally, saying she shares "the grave anxiety" that their families feel about their safety and security.

"The trial which is going on right now we consider to be a step toward the release and the return home of these two young women," Clinton told reporters after meeting with Turkish Foreign Minister Ahmet Davutoglu in Washington.

She said the US has been communicating to the North Koreans through the Swedish ambassador, who has met with the two women on three occasions. Washington has no formal diplomatic relations with Pyongyang.

"He has helped to facilitate the delivery of materials and the passing of messages," she said.

Clinton said she hoped the trial would be "resolved quickly" and that the two reporters are released.

The trial of Chinese-American Laura Ling and Korean-American Euna Lee for "hostile acts" began on Thursday, according to the North's Korean Central News Agency, but there have been no updates on the trial since.

The pair was arrested March 17 at the Chinese-North Korean border, where they were working on a story for the online broadcaster Current TV, which was co-founded by former US vice president Al Gore.

They were reportedly researching a story on North Korean refugees at the Tumen River separating the two countries. The details of their arrest by North Korean border guards remained unclear.

If found guilty of illegal entry, which according to observers seems highly likely, the two women face several years in prison and a sentence of up to 10 years of forced labour if found guilty of "crimes" against North Korea.

North Korean observers have speculated that the regime in Pyongyang wants to use the detained journalists as a way to win concessions in potential negotiations with the United States.

The United States at the moment is debating with other UN Security Council members on how to punish North Korea for its May 25 nuclear test, which was internationally condemned.(dpa)