MANILA (UPDATE) – President Rodrigo Duterte on Monday said he told Russian Prime Minister Dmitry Medvedev that he is about to "cross the Rubicon" with the United States, in what could be his most explicit expression of his desire to loosen ties with the Philippines’ long-time treaty ally.

Duterte revealed this as he made yet another jab at Western powers over what he believes were unjust criticisms of his war on illegal drugs.

He said the Philippines may need Russia's help if the Philippines distances itself from the United States.

“I’ve been talking with Prime Minister Medvedev. One-on-one kami. Walang nakalaam noon. I said, ‘I think I am about to cross the Rubicon between me and the US, at least for the 6 years. I would need your help and everything - trade, commerce. I will open up,’” he said.

[I’ve been talking with PM Medvedev, one-on-one. No one knew about it. I said, "I think I am about to cross the Rubicon between and the US, at least for 6 years. I would need your help and everything - trade, commerce. I will open up".]

Duterte also said he is willing to embrace China, a strategic rival of the U.S., as he shrugged off a warning from debt-watcher Standard and Poor’s that his bloody war on drugs and tough rhetoric raised questions on the predictability of the country’s economic policies.

“I have talked to Xi Jinping. I’m going to China. I will open up all avenues of trade and commerce. They can come in,” he said.

Duterte announced his plan to seek closer economic ties with China and Russia, with which the US has clashed with on various issues, as the Philippine peso hit a seven-year low which analysts say was connected to growing investor concern over Duterte’s unpredictability.

• READ: Duterte: 'Gusto ko si Putin'

• READ: Duterte: Deals with China, Russia 'in the pipeline'

The rising death toll in Duterte’s war on drugs has alarmed the US and other Western governments and institutions. Undaunted by the criticisms, Duterte instead pointed to the US and other Western nations’ “hypocrisy” over the ills of their respective societies and their wars in the Middle East.

Duterte grabbed international headlines for his expletives aimed at the U.S. government and United Nations secretary-general Ban Ki-moon, which have both raised concerns over his policies.

He also cursed at the European Union for calling him out over drug-related killings.

Despite being hostile once more towards the US, Duterte, later clarified to reporters that he is not yet ready to break ties with the U.S., "but we will open up alliances with China."

Asked what he meant by "crossing the Rubicon" with the U.S., he pointed to the Mutual Defense Treaty (MDT), which allows the US to come to the rescue should the Philippines be attacked by another country.

"But in the U.S. Constitution, it says that before a president can declare war with anybody in defense of an ally, he has to get Congress' permission to go to war. That is the problem," he said.

"The Congress will not give him authority. What will happen to us?"

Insisting that he will pursue an “independent foreign policy,” Duterte earlier asked that U.S. forces in Mindanao leave the country, only to take it back later, saying that the Philippines needs the U.S. in confronting China over the disputed South China Sea.

• READ: Philippines needs US in sea row with China: Duterte

Duterte’s latest tirade is yet another indication that the Philippines-US ties will be put to test under the new Filipino leader.

The tough-talking president has been warm towards Beijing despite the latter’s actions in the South China Sea, such as the blocking of Filipino fishermen in Panatag (Scarborough) Shoal off Zambales province.

He even said it would be “very undiplomatic” for the Philippines to demand from China that it allow Filipino fishermen to enter the resources-rich shoal.

Duterte is set to visit China and Japan in October, Palace officials said. He said he may also later go to Russia.

The latest tirades by Duterte towards the US came before the scheduled joint exercises between the two allies in October. Duterte said there is nothing he can do about it, as he does not want to embarrass Defense Secretary Delfin Lorenzana.

“There’s supposed to be a war game, it is already there. Ayaw ko na mapahiya ang, sila Defense Secretary Lorenzana, ‘yung mga military natin, go ahead,” he said.

[There’s supposed to be a war game, it is already there. I don’t want to embarrass Defense Secretary Lorenzana and the military. Go ahead.]

Nonetheless, he stressed his position ruling out participation in any joint patrols with the US in the disputed sea.