SEOUL - Former U.S. President Bill Clinton left North Korea on Wednesday with two American journalists whose release he secured in a meeting with the hermit state's leader, possibly opening the way to direct nuclear disarmament talks.

President Barack Obama called the families of Laura Ling and Euna Lee to express relief at their release, but a U.S. official said Pyongyang would face deeper isolation if it continued provocative behavior that has included recent nuclear and missile tests.

North Korea had agreed in advance that Clinton's trip -- which the White House called a private one -- would not be linked to the nuclear issue, said the official, speaking in Washington.

Analysts said Washington faced a risky task of trying to convince Pyongyang to give up dreams of becoming a nuclear weapons power without being seen to reward it for repeated military acts or ignoring the demands of others in the region.

President Clinton has safely left North Korea with Laura Ling and Euna Lee. They are en route to Los Angeles where Laura and Euna will be reunited with their families, Clinton spokesman Matt McKenna said in a statement.

The two, who work for Current TV, an American TV outlet co-founded by Clinton's vice president, Al Gore, were arrested in March for illegally crossing into the North from China.

They were each sentenced to 12 years hard labor in June in what many analysts said was aimed largely at trying to give Pyongyang some leverage with Washington.

Television footage showed the two journalists wearing green and red shirts and carrying luggage, greeted by Clinton as they boarded a plane. Clinton put his hand over his heart and then gave a final salute to North Korean officials at the airport.

WHAT WAS DISCUSSED?

Financial markets in Tokyo and Seoul largely ignored the visit although some South Korean traders said it did add a more positive atmosphere to what has been a string of negative reports over the North in recent months.

Washington denied North Korea's claim that Clinton had brought a message from Obama.

But there were questions about what Clinton had discussed with North Korean leader Kim Jong-il beyond the fate of the two reporters and what North Korea might expect in return for their pardon. The U.S. official said Clinton likely expressed his view on North Korean denuclearization in talks with Kim.

In North Korean media photographs of the meeting, Kim was smiling and looked in reasonable health after speculation he was seriously ill. Kim was suspected of suffering a stroke last year.

Regardless of what the U.S. administration says, the Clinton and Kim meeting signals the start of direct bargaining ... It's a matter of time when U.S.-North bilateral talks begin, South Korea's Chosun Ilbo daily said in an editorial.

Nicholas Szechenyi, Northeast Asia expert at the Center for Strategic and International Studies in Washington, said the biggest risk was that North Korea would demand a similar U.S. approach to the nuclear issue.

North Korea last year quit five years of on-and-off six-party negotiations with the United States, China, Japan, Russia and South Korea and has since suggested it will only talk with Washington.
We've seen this pattern before and it could send a very bad signal to the region if the administration suddenly shifts to a bilateral approach, said Szechenyi.

That is a cause for concern in Seoul and Tokyo.

South Korea and Japan both have politically sensitive concerns about citizens held in North Korea.

REGIONAL CONCERNS

I think the U.S. should resolutely reject bilateral talks. They won't be accepted by other East Asian countries, said North Korea expert Zhang Liangui at the Central Party School in China.

If these bilaterals touch on regional security issues, at the very least Japan and South Korea would be dissatisfied. If China is sidelined, it would also have an adverse reaction.

Pyongyang, craving the recognition that direct negotiations with the Obama administration would bring, painted the meeting between Clinton and Kim as high-level talks.

(The two) had candid and in-depth discussions on the pending issues between the DPRK (North Korea) and the U.S. in a sincere atmosphere and reached a consensus of views on seeking a negotiated settlement of (the two journalists), the North's KCNA news agency reported.

In comments that could well make U.S. officials wince, KCNA said: Clinton expressed words of sincere apology to Kim Jong Il for the hostile acts committed by the two American journalists against the DPRK after illegally intruding into it.

The U.S. official said Clinton did not offer any apology from Washington.

Clinton, husband of Secretary of State Hillary Clinton, was the highest-level American to visit the reclusive state since his secretary of state, Madeleine Albright, went there in 2000.

(Additional reporting by Jack Kim in Seoul, Lucy Hornby in Beijing, Paul Eckert in Washington, Editing by Dean Yates)