MANILA — Resupply missions to the BRP Sierra Madre on Ayungin Shoal have been met with stiff resistance and aggressive maneuvers by Chinese ships in recent weeks.

A Chinese Coast Guard vessel used a water cannon to try to drive away M/L Kalayaan, a civilian boat operated by the municipality of Kalayaan in Palawan, during the resupply mission last week.

Attempts to block another mission in late October resulted in collisions between Chinese and Philippine vessels, including the coast guard's BRP Cabra.

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But why does the Philippines rely on civilian ships — the Philippine Coast Guard and contracted boats — to resupply a Philippine Navy ship?

Speaking on ANC's "Headstart", PCG Commodore Jay Tarriela acknowledged that resupply missions are "definitely a military operation."

He said, though, that the Philippines wants "to show the world that we are in alignment with the regional norm of not militarizing the dispute."

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Tarriela said the country does not want to escalate tension in the region by sending Navy ships to the area.

Cagayan de Oro Rep. Rufus Rodriguez has suggested resupplying the BRP Sierra Madre by air to avoid putting civilian crews and boats in danger.