North Korean leader Kim Jong-il wrapped up his week-long trip to Russia and China, where he struggled to pave the way for resumption of the long-stalled regional nuclear disarmament talks and economic support.

Kim returned home via train on Saturday, greeted by his youngest son and apparent successor Kim Jong-un, who had been waiting at the border railway station, Pyongyang’s official Korean Central News Agency said.

The leader’s trip had been “successful,” it said. Kim had expressed his willingness to rejoin the six-nation denuclearization talks at an early date and to allow a Russian gas pipeline to South Korea through his country during the two-nation visit.

The tour by Pyongyang’s reclusive leader came at a sensitive time as his impoverished country is struggling to secure more outside assistance ahead of the 100th birthday of its late founder Kim Il-sung, the father of the incumbent Kim.

The ironfisted regime has promised its starving people that a “powerful, prosperous” nation will be built by the centennial of the birth of its founder, a goal it is determined to achieve ahead of a power transfer to 26-year-old heir-apparent, Kim Jong-un.

The communist state hopes to persuade dialogue partners to restart the six-nation nuclear disarmament talks, through which it had received food and fuel for years until the negotiations came to a halt at the end of 2008. The talks involve the two Koreas, China, Russia, the U.S. and Japan.

With Seoul, Washington and Tokyo still lukewarm to the resumption after its deadly attacks against South Korea last year, it is important for North Korea to secure support from China and Russia to resume the talks.

Kim started off the two-nation trip on Aug. 20, making his first stop at an eastern Russian city where he met with President Dmitry Medvedev.

While in China, Kim toured factories and industrial zones in the northeastern provinces of Jilin and Heilongjiang, once again indicating his country’s willingness to expand economic cooperation with allies.

The 69-year-old leader of Pyongyang also told Chinese officials he was willing to impose a nuclear test and production moratorium, and unconditionally return to the six-party talks, echoing the commitment he made to Medvedev.

The communist North is also expected to soon take up Moscow’s longstanding proposal to pipe Siberian natural gas to South Korea through his country’s territory.

Viktor Ishaev, Russia’s presidential envoy to the Far East Federal District, quoted Kim as telling him separately that North Korea will permit the pipeline to go through its territory if Russia and South Korean sign a contract on the project, according to Russia’s Interfax news agency.

The proposed pipeline would stretch more than 1,700 kilometers and start transporting volumes of up to 10 billion cubic meters per year. South Korea also supports the plan.

Once the rare deal is finalized, Pyongyang, which has relied heavily on outside aid to feed its population of 24 million since the late 1990s, could earn up to $100 million each year, according to Seoul’s estimation.

But actual results of Kim’s trip remain to be seen as Seoul and Washington appear cautious to fully accept his promise as honest.

South Korea, still trying to overcome hard feelings toward its northern rival for last year’s deadly attacks, has been downplaying Kim’s promise as “vague” and “somewhat ceremonial.”

“We haven’t been able to decide on the exact intentions of North Korea based merely on what was announced by the Russian presidential office,” Shin Maeng-ho, vice spokesman of South Korean Foreign Ministry, told a recent press briefing in Seoul.

Washington calls the reported offer “welcoming but insufficient,” noting Pyongyang’s silence over its new uranium enrichment facilities which are seen as a second path to developing nuclear weapons.

North Korea is believed to have enough weaponized plutonium for at least six atomic bombs. The North conducted two plutonium-based weapons tests each in 2006 and 2009.

The country also unveiled its uranium enrichment facility to outside experts in November.

By Shin Hae-in (hayney@heraldcorp.com)