MANILA - Canada continues to work towards resolving the problem over a private firm's garbage shipment to the Philippines in 2013 after the government tried but failed to take the waste back, Canadian Prime Minister Justin Trudeau said Tuesday.

In a press conference on the sidelines of the Association of Southeast Asian Nations Summit, Trudeau said he and President Rodrigo Duterte touched on the matter during informal talks Tuesday morning.

"We also discussed the garbage issue which has been a long-standing irritant and I committed to him as I am happy to commit to you all now that Canada is very much engaged in finding a solution on that," he said.

Trudeau said the Canadian government has worked around its laws to take back the garbage shipment but was barred by restrictions.

"Canadian legal regulations prevented us from being able to receive the waste back to Canada. We had legal barriers and restrictions that prevented us from taking it back, but that's done now," Trudeau said.

There are still questions being discussed, he said, such as "who will pay for it, where the financial responsibility is."

Ontario-based private firm Chronic Inc had imported to the Philippines at least 55 containers filled with trash, including household waste, in 2013. They were misdeclared as plastic scraps.

Intercepted in Manila, some of the containers were later sent to a landfill in Capas, Tarlac.

During Trudeau's first visit to the Philippines for the Asia-Pacific Economic Cooperation Summit in 2015, he vowed to find a solution to the garbage problem.

Two years since, at least 26 out of the 55 containers filled with "blue bin" trash are still left in Manila's ports, said Geri Geronimo Sañez, chief of the Department of Environment and Natural Resources' Hazardous Waste Management Section.

"It's a blue bin waste. That's paper, dry plastic generated from the kitchen. I have not seen any syringe, any diaper. It's not hazardous, but it's waste still," Sañez told reporters.

Most of the trash were taken away from the ports as it was used as "evidence" against the companies involved in the mess, the official said.

Chronic Plastics Inc, the Valenzuela-based consignee, is facing charges for violation of Republic Act 9003 or the Ecological Solid Waste Management Act and the 1995 Basel Convention on the Transboundary Movement of Hazardous Wastes and Disposal, Sañez said.

The international convention, to which both Canada and the Philippines are signatories, provides that “the exporting country must take back the waste materials if the receiving country refuses to accept them.”

Canadian officials earlier said there was no violation of the Basel Convention as the shipment do not contain hazardous waste.

Sañez confirmed that there were "no syringes and no diapers" found in the shipment but said the Canadian side may still be liable for misdeclaring the contents of the containers.