MANILA - The Philippine Competition Commission said it was difficult to investigate the existence of the alleged "onion cartel" but added that they hope to finish the probe in 2 to 3 months, or before the end of the year.

A cartel is allegedly behind the spike in the prices of onion in the past months, according to some farmers' groups and legislators.

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The PCC earlier said it has been investigating a possible onion cartel since November last year.

But PCC Chairperson Michael Aguinaldo on Monday said it was not easy to the storage facilities of the alleged cartel.

Aguinaldo said there should be evidence first that a facility is indeed hoarding onions. But when they do inspect, more often than not, the onions have already been brought to another place, he said.

"What they did was to visit different cold storage facilities, unfortunately pagdating nila wala na doon ang sibuyas," said Aguinaldo.

The PCC said it will check all parts of the supply chain.

He also said they hope that someone would shed light on the issue or discretely report to them.

"Most likely traders, but when it comes to agricultural products, it's not just one middleman, usually many traders in between, that in itself is a challenge," he said.

Late last year, prices of onions surged to as high as P700 per kilo, which prompted the government to approve importation to boost the supply and lower the prices.

The spike in the prices of onion and other commodities was a factor in the high inflation in recent months.

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