As Russian President Vladimir Putin glided through the crowd-lined streets of Pyongyang atop a luxury Mercedes-Benz alongside his North Korean host Kim Jong Un last week, the two autocrats' most important partner was watching from the sidelines hundreds of miles away in Beijing.
Five years ago, Xi Jinping was offered the same open-top ride with Kim when he became the first Chinese leader to visit Pyongyang in 14 years. At the time, the two leaders vowed to strengthen ties and deepen cooperation, but the language paled in comparison with the "breakthrough" new partnership struck by Kim and Putin.
In a wide-ranging treaty spanning political, trade, investment, and security cooperation, North Korea and Russia pledged to use all available means to provide immediate military assistance in the event the other is attacked.
Putin said Russia and North Korea have ramped up ties to a "new level." Kim, meanwhile, called the new "alliance" a "watershed moment" in bilateral relations.
The new landmark defense pact agreed by the two nuclear-armed regimes rattled the United States and its Asian allies. Japan voiced "grave concerns" about Putin's vow not to rule out cooperation with Pyongyang on military technology. South Korea responded by convening an emergency national security meeting and said it would now consider sending arms to Ukraine.
In contrast, the reaction from China, the main political and economic patron for both Russia and North Korea, has been all but muted.
A spokesperson for China's Foreign Ministry declined to comment on the treaty, calling it a bilateral matter between Russia and North Korea.
Beneath the official reticence, however, China is likely watching warily, analysts say.
The deepening ties between two wayward autocrats risk creating new uncertainty for Xi, who needs peace and stability in Northeast Asia as he grapples with a raft of domestic challenges, especially the slowing economy.
Beijing is worried that Moscow's assistance to Pyongyang – especially on military technology – would further enable and embolden the erratic Kim regime, which has drastically accelerated the buildup of nuclear weapons and missile programs, said Liu Dongshu, an assistant professor focusing on Chinese politics at the City University of Hong Kong.
"When it comes to the North Korea issue, China aims to control the situation and prevent escalation, but it also does not want North Korea to completely collapse either" – a scenario that Beijing fears would allow the US to extend its control right to its doorstep, Liu said.
Previously, Russia had been largely aligned with China on the issue, but its desperate need for North Korea to support its grinding war in Ukraine risks undermining the delicate balance.
Russia has received more than 10,000 shipping containers – the equivalent of 260,000 metric tons of munitions or munitions-related material – from North Korea since September, according to a US statement in February. Both Russia and North Korea have rejected the claim.
And while the US has accused China of providing Russia with dual-use goods that bolster the warring nation's military industrial complex, Beijing has refrained from offering direct military assistance to Putin and has steered clear of supporting Kim's nuclear and missile programs.
"If Putin provides more support to North Korea on nuclear issues, including some technical assistance, it will become more difficult for China to control the situation on the Korean Peninsula," Liu said.
Keep reading about the mutual defense pact.
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