MANILA - President Rodrigo Duterte's decision to terminate the country's Visiting Forces Agreement with the United States is a "tactical" decision that indicates he may have something up his sleeve, his spokesman said Thursday.

"The decision of the President to terminate the VFA is a studied decision. It is a tactical and strategic decision as stated by him," Salvador Panelo told reporters in Malacañang.

"In other words, he (Duterte) has something in his mind which he has not shared."

The President on Wednesday night said he had long thought about terminating the military agreement that was signed in 1998, denying allegations it was an impulsive decision.

He said he started thinking about it when the US Senate passed a resolution calling on his American counterpart Donald Trump to impose sanctions on Philippine government officials supposedly behind the detention of his staunch critic Sen. Leila de Lima.

“Noon pa lang, 'yung utak ko gumagalaw na. Ganoon ako. Hindi ako naghihintay. I just announce late,” Duterte said in an interview on the sidelines of the 69th anniversary celebration of the Department of Social Welfare and Development in Quezon City.

(I have long thought about this. I don’t wait. I just announce late.)

• No VFA? Manila can seek military aid from Russia, China: Palace official

Duterte's recent pronouncement to terminate the VFA came after the cancellation of the US visa of Sen. Ronald "Bato" Dela Rosa, his longtime ally who spearheaded the administration's bloody war on drugs while serving as national police chief from 2016 up to 2018.

Dela Rosa surmised it has something to do with concerns expressed by the US on alleged extrajudicial killings in the country amid the government's harsh anti-narcotics campaign.

The VFA, which came into force in 1999, covers the conduct of American soldiers in the Philippines. Manila last week started the process of scrapping it on Duterte's orders.

Under the agreement, it will be deemed terminated 180 days from the date on which either party gives the other party a notice in writing.

NO EFFECT ON OTHER MILITARY DEALS

Panelo clarified that abrogating the VFA will not affect Manila's such other military agreements with Washington as the Enhanced Defense Cooperation Agreement, which allows greater rotational presence of US troops in the country, and the Mutual Defense Treaty, which lets the parties come to each other's defense in case of an attack from another party.

Terminating the VFA is an opportunity for the Philippines to strengthen its defense capability independently, Panelo said.

"It's about time that we, as a country, rely on our own resources. We cannot be relying on others. We have to strengthen our capability in defending ourselves from foreign intrusions," he said.

Lawmakers, meanwhile, are set to review the country's defense pacts with the US and other countries next week, to see if these are still aligned with Philippine interests, Sen. Aquilino Pimentel III said.

Pimentel said the senators will look as well into problems in implementing the agreements and how these were handled.

• Senate to review VFA, other defense pacts

After assuming the presidency in 2016, Duterte sought to establish an independent foreign policy that relies less on the United States, its longtime and only treaty ally, and forges improved relations with China and Russia.