Philippine President Rodrigo Duterte criticized the U.S. for halting a planned arms deal, calling those behind the decision "fools" and "monkeys". (Reuters)

It's only Wednesday, but President Rodrigo Duterte must be ready for the weekend.

Less than two weeks after his trip to China and his call for a “separation” from the United States, the president of the Philippines is for the first time feeling the effects of what seems to be — to some at least — a concerted effort to alienate his allies.

The first hit: the defection of former president Fidel Ramos. Duterte's camp confirmed Wednesday that Ramos, Duterte's China envoy, has resigned just four months into the president's term.

The news came after Ramos, who helped Duterte get elected, put out his second scathing critique of the president's short tenure. The piece, published Sunday, accused Duterte of “unwittingly shooting himself in the mouth” and taking "101.5 million Filipinos” down with him by insulting allies.

“He may claim that to be more ‘insulting than friendly’ to our long-established allies is part of his God-given ‘destiny.’ But, this is obviously wrong, and full of S …. T!!!,” Ramos wrote.

In an earlier letter, Ramos called Duterte's first 100 days as president a “huge disappointment and letdown.” Ramos faulted Duterte for a bloody campaign against suspected drug users and dealers that has claimed thousands of lives, and he criticized his anti-U.S., anti-U.N. rhetoric.

Ramos, a former chief of the armed forces, was particularly critical of Duterte's comments on U.S.-Philippine military ties. Over the past few months, Duterte surprised many by calling for the withdrawal of U.S. Special Forces from the southern island of Mindanao and the cancellation of future U.S.-Philippine military exercises, only to back down days later.

“Are we throwing away decades of military partnership, tactical proficiency, compatible weaponry, predictable logistics and soldier-to-soldier camaraderie just like that?” Ramos asked.

Philippine President Rodrigo Duterte reiterated his desire to end military relations with the U.S. on Oct. 26, saying, "I want in the next two years my country free of the presence of foreign military troops, I want them out...This will be the last maneuver, war games between the United States and the Philippines military." (Reuters)

Though opinion polls suggest that Duterte still enjoys strong public support, Ramos's comments will no doubt resonate, particularly among those with ties to the military and foreign policy elite.

It will be tough for Duterte's team to spin Ramos’s departure as anything other than a massive loss. Responding to questions about Ramos's critique, a presidential spokesman called Ramos “invaluable” to the administration. Another aide told the media that he was “really surprised” by the resignation.

A second sour surprise: news that the United States may halt the sale of 26,000 M4 assault rifles to the Philippine National Police.

Reuters reported Tuesday that the State Department will stop the weapons sale because of opposition from Sen. Benjamin L. Cardin (Md.), the top Democrat on the U.S. Senate Foreign Relations Committee and a vocal critic of Duterte's "drug war."

Although the State Department did not comment to confirm or deny Reuters's reporting, the head of the Philippine National Police said in a statement that he was “saddened” by the news. Duterte, meanwhile, tried to shrug it off, dismissing the report as a U.S. “scare tactic” and saying the necessary weapons can be purchased somewhere else — like Russia.

Duterte is partly right. Stopping the sale of 26,000 guns is a small gesture, compared with the $9 million in aid that the State Department will give to counternarcotics and law enforcement programs in the Philippines in 2017 and with the $32 million that Secretary of State John F. Kerry pledged this summer for Duterte's law enforcement programs.

But it's a move that is intended to show that some U.S. funding for the Philippines can and will be cut if the president's human rights abuses and anti-U.S. rhetoric continue.

“Look at these monkeys, the 26,000 firearms we wanted to buy, they don't want to sell,” Duterte said during a televised speech Wednesday, adding that U.S. lawmakers were “fools.”

“We have many homemade guns here,” he added, according to Reuters.

Phelim Kine, deputy director of Human Rights Watch's Asia division, called it “the first real US move to put teeth in its criticism of the spiraling death toll of Duterte’s 'drug war.'”

Brian Murphy contributed to this report.

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