MANILA (UPDATE) - It will be "more beneficial" for the Philippines to review its Visiting Forces Agreement (VFA) with the United States instead of terminating the military pact, Foreign Affairs Secretary Teodoro Locsin Jr. said Thursday.

The Philippines may lose billions-worth of assistance and even its good relations with regional neighbors should it scrap the VFA, Locsin said in a Senate inquiry that sought to review the benefits of the military accord after President Rodrigo Duterte threatened to abrogate it last month.

"While the Philippines has the prerogative to terminate the VFA anytime, the continuance of the Agreement is deemed to be more beneficial to the Philippines compared to any benefits were it to be terminated," Locsin said in his opening statement.

"Our contribution to regional defense is anchored in our military alliance with the world's last superpower," he said.

The VFA and the Enhanced Defense Cooperation Agreement (EDCA) operationalize Manila's nearly 70-year-old Mutual Defense Treaty (MDT) with Washington. The EDCA allows greater rotational presence of US troops here, while the VFA governs the conduct of American uniformed personnel while in the country.

"The US may see no need to continue with EDCA without the VFA because its military capability depends on human regulators whose behaviors need to be regulated," he said.

Locsin also outlined how much the Philippines could lose should it terminate the VFA.

• IN NUMBERS: How beneficial is VFA to the Philippines?

OTHER ALLIANCES?

Locsin said it was "inconceivable" for the Philippines to have a defense pact with nations other than the "world's last superpower."

"It is rationally inconceivable to have an MDT with any military power except one that is too far to meddle in internal affairs, but with a strong and long enough reach to hit the mutual enemy," he said, noting that Beijing and Moscow earlier said that they do "not want to take on the US."

Duterte earlier ordered the termination of the VFA after the US canceled the visa of Sen. Ronald Dela Rosa, his long-time ally who spearheaded the government's war on drugs when he was national police chief.

Manila turned away from its traditional alliance with Washington in 2016 after Duterte rose to the presidency. Duterte criticized then-US President Barack Obama who spoke against his intensified campaign against narcotics that left thousands of suspected drug users and peddlers killed.

Duterte has also forged closer ties with Beijing, which provided loans to fund the government's massive infrastructure push.

US 'INSULTED' PH

Despite recognizing the importance of US aid to the Philippines, Locsin also underscored that it was "logical" to review the VFA after American politicians "disrespected" the country's sovereignty when they sought the release of a Filipino who was detained in accordance with the law.

Locsin did not name who he was referring to but some US Democratic senators earlier urged the Philippines to release Sen. Leila de Lima, a fierce Duterte critic who has been detained since February 2017 on drug-related charges.

"The VFA is the logical target when the country's sovereign justice system, modeled after the US, is disrespected," Locsin told senators.

"When US senators demean the Philippine justice system... It insulted the most basic aspect of sovereignty: the monopoly of justice within its territory," he said.

The DFA is in the process of communicating with their US counterparts to address some "irritants," Locsin said, without elaborating on the issues expected to be discussed in a meeting next month.