Relations are souring quickly between the Philippines and the United States, as President Rodrigo Duterte and 250 Filipino business executives head to China, a historic rival, later in October to discuss partnership prospects.

“China has repeatedly invited me. I have accepted the offer,” Duterte told reporters, announcing the visit, which is scheduled for October 19-21.

According to Reuters, Duterte’s China visit is already oversubscribed, with business and government officials all eager to discuss multi-sector economic cooperation with Beijing. There were initially supposed to be fewer industry professionals, but the number has gone up to 250, Trade Undersecretary Nora Terrado told Reuters, adding that the delegation’s unusual size is due to the fact that the meeting had only been agreed on a month ago.

Duterte criticized US President Barack Obama for “arrogance” as he announced the visit – despite the Philippines being a key US ally in the region. The relationship has been strained recently, however, following a series of inflammatory remarks from Duterte in response to Obama’s criticism of the Philippines leader’s tactics in the domestic war on drugs.

Until recently, though, the two planned joint military drills in the South China Sea, a territory China lays claim to. Those plans were put on hold on October 8, when Duterte said this year’s annual naval exercise would be the last.

“For as long as I am there, do not treat us like a doormat because you’ll be sorry for it,” Duterte threatened. “I will not speak with you. I can always go to China.”

However, the contested territories of the South China Sea remain an unresolved issue between the Philippines and China. On July 12, The Hague ruled that Beijing’s claims to waters in the area infringe on Manilla’s sovereign territory. This was expected to put a damper on Chinese-Philippine relations even further.

But amidst the deterioration of relations with Washington over the past month, Duterte has threatened he would retaliate by turning to China, and he appears to be making good on that promise.

“We do have a very popular president and the president decided that he wanted to have a better relationship with China,” Francis Chua, chairman emeritus of the Philippine Chamber of Commerce and Industry, said. “We are neighbors… this is actually what the president is thinking: instead of fighting, why don’t we just become friends?”

The sentiment was echoed even more colorfully by Beijing’s ambassador to the Philippines, Zhao Jianhua: “The clouds are fading away. The sun is rising over the horizon, and will shine beautifully on the new chapter of bilateral relations.”

No concrete Philippine-Chinese deals have been set in stone, but discussions held on day one of Duterte’s visit should shed more light on that. There have already been suggestions in the sphere of infrastructure and transport, with Chinese firms expressing a wish to modernize railroads in the Philippines.

No mutual defense prospects have been voiced as of yet.

Experts believe the Philippines could stand to gain significantly from cooperation with China, especially on pressing issues such as energy, infrastructure and unemployment.