Metro Manila (CNN Philippines, July 26) — Bangko Sentral ng Pilipinas (BSP) Governor Benjamin Diokno is backing the proposal to convert ₱20 bills into coins, which will be out next year.

While the design of the new coins is still in the works, Diokno said these “will also have the face of (President) Manuel Quezon,” referring to the current orange bills in circulation.

Quezon is the second President of the Philippines, who led the country during American occupation from 1935 to 1944.

“It's still being studied, but we look at the numbers. Do you know that it costs us ₱2 to print a 20-peso bill? And that bill is the most used currency,” Diokno told CNN Philippines in an interview. “In fact, I saw a ₱20 bill with my signature, it’s already tattered.”

Diokno, the former Budget secretary, was appointed by President Rodrigo Duterte to serve the remaining four-year term as BSP chief last March. The central bank launched new bills bearing Diokno’s worm-like signature only last July 3.

The central bank has the sole power to print and circulate cash used in the Philippines, which is all done at the BSP’s Security Plant Complex along East Avenue in Quezon City.

The BSP said last week that the new coin proposal stems from a study conducted by the University of the Philippines, which recommended the shift from paper to metal coins for durability. Being the most used denomination, ₱20 bills are easily spoiled and is the fastest to be returned to the BSP for replacement.

Diokno said the coin will cost more to produce, but will be more “cost-efficient” as these could last for 10 to 15 years.

Currently, the ₱20 bill is the lowest denomination among banknotes. The central bank previously converted the brown ₱10 bills into coins.

New coin designs were rolled out last year, which made all coins silver but came in varying sizes and embossed designs.

The proposal is pending before the BSP’s Committee on Currency Design and Enhancements, and will still have to be approved by the Monetary Board and by Malacañang before coin minting can start. Diokno said the new coins could be ready by “maybe next year.”