China isn’t officially represented in the historic talks between U.S. President Donald Trump and North Korean leader Kim Jong Un, but that hasn’t stopped Beijing from making its presence felt.

Kim arrived in the city state Sunday aboard a Boeing 747 operated by Air China Ltd., China’s state-run flagship carrier. The flight was both a potent display of China’s industrial might—and a message that the country had North Korea’s back.

“All these symbols are worth reading into,” Shawn Ho, an associate research fellow at the S. Rajaratnam School of International Studies, told a panel discussion Monday in Singapore. “China continues to have a major stake in the Korean Peninsula,” he said, and it “seems to be ready to support north Korea.”

Chinese President Xi Jinping—who also travels on an Air China 747—has a lot at stake in the first-ever talks between a sitting U.S. president and a supreme North Korean leader. If they fail, Xi will be looking to avert chaos or conflict on his border. If they work, he risks an old ally being drawn closer to America.

‘Chinese Plane’

Xi’s contribution of the jet was necessary because Kim lacks the aircraft and military reach needed to ensure his safety on the almost 5,000-kilometer (3,000-mile) journey from Pyongyang to Singapore. That’s one reason he wants to end international sanctions and develop his economy.

Air China shares rose 1.1 percent in Hong Kong trading Monday, outperforming a 0.3 percent gain in the benchmark Hang Seng Index.

Accepting such Chinese support might be seen as an admission of weakness for a leader whose image is based on the philosophy of “Juche,” or self-reliance. Interestingly, North Korea made no attempt to conceal the contribution, publishing a photo of Kim exiting the jet in the regime’s main newspaper Monday and repeatedly mentioning the “Chinese plane” in state media reports.

China’s foreign ministry, however, would only provide a short statement on the plane, despite repeated questions at a regular news briefing Monday in Beijing.

“As requested by the DPRK side, China’s civil airline offered a relevant service to the DPRK delegation,” ministry spokesman Geng Shuang said, referring to North Korea’s formal name.

Biggest Partner

China has repeatedly sought to assert it’s crucial role in the talks. As North Korea’s largest trading partner, China’s enforcement of United Nations sanctions helped bring Kim to the negotiating table, while also shielding his regime from Trump’s threats of military action.

The plane reflects China’s effort to show itself as a leader in issues of regional concern, said Chucheng Feng, co-founder of GRisk, a Hong Kong-based political risk consulting firm. “China cannot be absent on such occasions,” Feng said.

Air China announced last week that it would resume regular flights between Beijing and Pyongyang after a six-month hiatus—the latest sign that the “maximum pressure” campaign on North Korea may be easing. Air China declined to comment Monday on Kim’s use of the plane.

In the run-up to the summit, Kim visited China twice to meet with Xi. During their March meeting in Beijing, Xi told Kim that China had made a “strategic choice” to have friendly ties with North Korea, and that they would “remain unchanged under any circumstances.”

The plane is a way for China to say it still has a big role to play in the situation, said Paul Haenle, a former China director on the U.S. National Security Council who now heads the Carnegie-Tsinghua Center in Beijing. “China’s trying to stay engaged in the diplomacy and to not be a participant on the sidelines of this.”