MANILA — Foreign Affairs Secretary Teodoro Locsin, Jr. attempted to explain on Monday why only a tiny fraction of pledges from Beijing come to fruition, in response to accusations that aid from China was just "a pittance" compared to the amount of resources it takes from the Philippines.

Earlier in the day, retired Supreme Court Associate Justice Antonio Carpio said that of the $24 billion in loans and investments Beijing had promised to the Philippines, only 5 percent have materialized.

"Even if the entire $24 billion has materialized, that’s a pittance compared to the value of the fish, oil, gas and other mineral resources in the West Philippine Sea," Carpio told ANC.

But, according to Locsin, the dismal percentage was due to the government's prudence to protect "national interest."

"Less than 5 percent [because] Finance Secretary Sonny [Dominguez], unlike his predecessors, is careful for the national interest. He set up a take-it-or-leave-it-system. We decide what project. Put it out for loan or bid; best bid wins," Locsin said in a tweet.

He added that "Japan nearly always beats all with near 0 percent interest."

Critics have said the Philippines has entered into onerous deals with China, with Carpio warning that Beijing could seize natural gas deposits in the Reed Bank (Recto Bank) in the disputed waters if Manila is unable to pay the $62-million Chinese loan for the Chico River Irrigation Loan Agreement.

Carpio is a long-time advocate of the Philippines' sovereignty and a vocal critic of what he calls China's "creeping invasion."

• Carpio: China will continue creeping invasion by intimidation

Beijing has continued to ignore a 2016 arbitral ruling invalidating its 9-dash line claim over nearly all of the South China Sea, as President Rodrigo Duterte sought closer ties with the economic giant for his administration's infrastructure projects.

Duterte last week told the UN General Assembly that the Philippines "firmly rejects" any attempt to undermine the ruling.