The Philippine Senate voted Monday 12-0-8 to adopt Senate Resolution #337 that will ask the Supreme Court to rule if a sitting president can approve and terminate agreements with foreign governments without Senate concurrence.

The effort is being led by Senate President Vicente Sotto III, who is an ally of Philippine President Rodrigo Duterte but still supports the resolution. Sotto says that his stance on the topic is not an affront to the president but is “purely a question of law” that needs some resolution.

The crux of the matter is Duterte’s decision in early February to cancel, on his own authority, an agreement in place since 1998 called the Visiting Forces Agreement (VFA) that allowed U.S. troops legal authority to carry out military exercises and humanitarian assistance operations on a rotating basis.

Duterte is not a fan of the VFA and has made previous threats to cancel it but what is questionable about his latest action is that it seems to be based on a personal grudge with no consideration about how the VFA has benefitted the country.

In a recent article by Inquirer.net, former Foreign Secretary Albert del Rosario called the VFA with the United States “imperfect” but stressed its importance and benefits to the Philippines. He said in a statement, “Without the VFA, making the MDT (Mutual Defense Treaty) work would be more challenging, especially since we now have specific external threats as well as more devastating natural calamities.”

He referred to the 2013 Supertyphoon Yolanda where U.S. troops were able to readily come in to help in the aftermath while other countries could not enter with no such agreement in place.

It is thought that Duterte used the move against the VFA as retribution to the U.S. canceling the diplomatic visa of his longtime confidant Sen. Ronald “Bato” Dela Rosa, the former chief of police who is heavily implicated for human rights abuses and alleged extrajudicial killings during Duterte’s war on drugs.

Sotto added to his comments, "I respectfully adhere to the rule that, yes, the President of the Philippines is the sole representative of the country in foreign affairs. I do not intend to go against the tide. I just want clarity. We want clarity. And I hope that once and for all, the honorable Supreme Court shed light on this purely question of law.”

The cancellation of the VFA will undermine efforts by the U.S. to counter China’s growing presence in the South China Sea and the loss of some strategic advantages but U.S. President Donald Trump did not seem too concerned saying that he was “fine” with the decision and that it would save the country some money.

The loss of the VFA will make it much harder for U.S. Departments of State and Defense to allocate funds from the U.S. Congress for other defense assistance programs to the Philippines. Duterte and his senators need to add that to the list of concerns as they wrangle over if Duterte can act alone or needs senate ratification on such decisions.