Philippine Customs Commissioner Sunny Sevilla said he submitted his resignation Wednesday, citing pressure to promote people without considering their merit for the jobs.

"I'm feeling the political patronage" pressure, Sevilla said at a briefing in Manila on Thursday, without elaborating. "I hope the next commissioner will do a better job than me. The path of good governance is in deep danger in customs."

Sevilla's departure would be a setback to President Benigno Aquino III's efforts to make a lasting dent in corruption before he steps down in June next year. Tasked by Aquino to clean up an agency known for graft, the former Goldman Sachs Group Inc. trader has reduced smuggling while raising revenue.

Customs collection, which accounts for about 20 percent of government revenue, rose 21 percent last year. The agency's 2015 collection target is not achievable due to lower oil prices and revenue will probably be little changed from last year, Sevilla said this week.

During his term, Sevilla investigated his staff, suspended permits of some companies and brokers, clamped down on the release of illegal rice shipments and set up a public price database of frequently imported goods to make it easier to spot irregularities.

Sevilla said his resignation will take effect once a replacement is made, and he hasn't yet decided what to do next. Aquino's Communications Secretary Sonny Coloma said he would comment on the custom chief's decision to quit at the regular media briefing later Thursday.