Before he was elected president, Philippine leader Rodrigo Duterte promised to use a jet ski to reclaim a disputed reef seized by China. Since taking office in June, he has extended the hand of friendship.

The tough-talking Duterte will bring up to 400 business leaders including some of the Philippines's wealthiest tycoons on a four-day visit to Beijing starting Tuesday. In doing so, he'll become the first Philippine leader invited to the capital by Chinese President Xi Jinping for one-on-one talks.

"Duterte's visit is the strongest signal so far that tensions between China and the Philippines have eased off," said Li Jinming, professor of international relations at Xiamen University's Research School of Southeast Asian Studies. "He's right now distancing the country from the U.S., but some of that is just rhetoric. We don't think he will or can cut the U.S. off. We'd be curious to know how long these icy ties can last. It might just be a temporary thing."