North Korean leader Kim Jong Un shakes hands with Chinese President Xi Jinping in Beijing, as he paid an unofficial visit to China, in this undated photo released by North Korea's Korean Central News Agency (KCNA) in Pyongyang March 28, 2018. KCNA | Reuters

North Korean leader Kim Jong Un's three-day meeting with Chinese President Xi Jinping in Beijing this week likely focused on a range of issues including economic ties, nuclear talks and the possibility of a second summit between Kim and U.S. President Donald Trump. But there's one topic that likely wasn't officially discussed despite its importance to North Korea's future: The prospect of Pyongyang joining China's continent-spanning Belt and Road Initiative, a project aiming to link more than 60 countries in Asia, Europe, Africa and the Middle East through overland and maritime routes. The isolated state is hungry for foreign investments, particularly in infrastructure, as U.N. sanctions take a toll on its economy. Many believe that's been a major reason underlining Kim's engagement with the international community over the past year or so.

Pyongyang's economic goal

Now that the head of state has made major strides in nuclear technology, he can focus on his other major policy goal —economic development, politics watchers say.

But to do so, Pyongyang needs help from its rich neighbors. The nuclear-armed nation is seeking more than $7.7 million in investment, the Seoul-based online newspaper NK News reported last month, citing information from a website run by North Korea's foreign trade ministry. Xi's Belt and Road project offers the perfect answer to those needs. China has historically been Pyongyang's largest trading partner. Pyongyang "would love to be part of Belt and Road," Dane Chamorro, a senior partner in the Asia Pacific division of Control Risks, a consulting firm specializing in politics told CNBC on Friday. Kim's government is waiting for an invitation so his country can get assistance on the construction of railway links and ports and other facilities, Chamorro said. Beijing also seems keen on Pyongyang's inclusion, with the Chinese government inviting a North Korean delegation to attend a Belt and Road summit in 2017 — but it's unlikely to take any action for now. Including Pyongyang in the BRI is "probably more trouble than it's worth" at the present moment, said Mintaro Oba, a former U.S. State Department official who specialized in the Koreas during the administration of former President Barack Obama. For one, sanctions still remain in place. Beijing, however, has called for those penalties to be eased.

It would also raise eyebrows in Washington and contribute to the perception that Belt and Road has low standards ... Mintaro Oba former U.S. State Department official

"It would also raise eyebrows in Washington and contribute to the perception that Belt and Road has low standards and primarily serves to deepen the dependence of other states on China," Oba said. Trump's White House is already skeptical of Beijing's activities overseas and has launched various initiatives to counter Chinese influence in Asia.

'Wait and see'