Assistant Secretary of State Daniel Russel talks to reporters in Manila after a meeting with Philippine Foreign Secretary Perfecto Yasay Jr. (Romeo Ranoco/Reuters)

Philippine President Rodrigo Duterte’s controversial statements and uncertainty about his intentions are causing distress in the United States and elsewhere, the top American diplomat for Asia said Monday.

Duterte has called President Obama a “son of a whore” and has told him to “go to hell.” Last week, he sensationally announced his nation’s “separation” from the United States and its embrace of China, but later, he partially walked back those remarks.

On returning home from a state visit to Beijing, Duterte said that he did not want to sever economic and military ties with Washington but that he wanted to underline that his foreign policy would not “dovetail” with that of the United States.

Duterte’s administration has also not followed through on his pledges to remove U.S. counterterrorism troops from the southern island of Mindanao and end annual military exercises with U.S. forces, with his cabinet members often appearing confused and wrong-footed by successive announcements.

Daniel Russel, assistant secretary of state for East Asian and Pacific affairs, flew to Manila on Sunday in an attempt to get clarity and spoke to reporters Monday after meeting with Philippine Foreign Secretary Perfecto Yasay Jr.

“I’ve pointed out to Secretary Yasay that the succession of controversial statements, comments and a real climate of uncertainty about the Philippines’ intentions has created consternation in a number of countries, not only in mine, and not only among governments,” Russel said.

“There is growing concern in other communities and the expat Filipino community, in corporate boardrooms as well,” he said. “That’s not a positive trend.”

The United States remains a “steady and trusted” partner of the Philippines and will continue to provide assistance, including in its “effort against the scourge of drugs,” Russel said. But he said Washington is concerned over the loss of lives in Duterte’s drug war, which is “bad for business as well.”

Since Duterte came to power in June, thousands of Filipinos have been gunned down by police in late-night drug operations or have been killed by assassins, often after being named by police. Last month, the president said he would be happy to slaughter millions of drug addicts in his country, comparing his campaign to Hitler’s massacre of Jews in the Holocaust.

The prospect of being lectured about extrajudicial killings in a meeting planned with Obama in September prompted a string of antagonistic and vitriolic remarks from Duterte about Obama and the United States.

Governments throughout Southeast Asia, especially those with claims to the waters of the South China Sea, have also been concerned about Duterte, amid fears he is being bought off by Beijing.

The Philippines took China to an international tribunal in the Hague over the South China Sea issue, winning an important victory in July after the tribunal ruled that China’s expansive claims to the disputed waters have no legal basis.

But Duterte has since agreed not to raise the tribunal’s ruling in international meetings and instead start bilateral talks with China over the issue. 

In return, he secured a Chinese pledge to step up investment and lending to the Philippines, especially for infrastructure. But it is far from clear that he has secured any concession in the maritime dispute.

On Sunday, Duterte said Filipino fishermen might soon be able to return to Scarborough Shoal, off his country’s northwest coast, for the first time since China took control of the area in 2012.

But Chen Xiangmiao, a research fellow at the National Institute for South China Sea Studies, in Hainan, China, said Beijing would not allow Philippine fishermen back onto the shoal.

“China will never open up the island to them,” he said. “China will not allow its sovereignty to be questioned.”

China’s Foreign Ministry did not respond directly to a question about whether a deal had been struck over fishing rights at Scarborough Shoal, saying only that both countries’ leaders had agreed to communicate openly about the South China Sea and to deal with differences. “So please rest assured that China and the Philippines will maintain enough political will to appropriately resolve any relevant issues,” spokesman Lu Kang said at a news conference.

Ian Storey, a senior fellow at the Institute of Southeast Asian Studies-Yusof Ishak Institute, in Singapore, said Duterte is “taking a big risk” in his approach to China, partly because the people of his country are enthusiastic about the United States and distrust China. 

If Beijing does not give access to Scarborough Shoal, “that’s going to go down pretty badly at home” in the Philippines, Storey said.

Duterte’s inconsistency and temperament, and his country’s history of foreign policy flip-flops, may lead to some wariness in Beijing.

“China should not simply pin all its hopes on Duterte’s unusual governance. China still has much to do to constantly expand its common interests with the Philippines and work for a complete turnabout in the South China Sea,” China’s state-sponsored Global Times said in an editorial Monday.

Congcong Zhang contributed to this report.