Philippines President Rodrigo Duterte has ordered Canadian waste shipped back to its country of origin, his spokesman says.
It is the latest move in a row between the two countries over the disposal of waste wrongly labelled as recyclable.
The Philippines has filed several diplomatic protests over the tonnes of refuse shipped between 2013-14.
Last week, Manila recalled its ambassador after Canada missed a 15 May deadline to retrieve the rubbish.
“As a result of this offending delay, the president has instructed the appropriate office to look for a private shipping company which will bring back Canada’s trash to the latter’s jurisdiction,” spokesman Salvador Panelo told reporters on Wednesday.
“If Canada will not accept the trash, we will leave the same within the territorial waters or 12 nautical miles out to sea from the baseline of any of their country’s shores.”
Mr Duterte, who is known for his outspoken style, had threatened last month to ship the waste back if the issue was not resolved.
The row relates to containers shipped to Manila by a private Canadian-based company and its Philippines-based consignees.
Canada has said it is working with the Philippines government to resolve the issue and has made an offer to repatriate the waste.
Manila says the containers, which arrived at Manila International Container Port, were falsely labelled as containing plastics meant for recycling and were in fact filled with tonnes of household waste.
Another inspection of the remaining containers in 2015 found they contained non-hazardous municipal waste, including household and street rubbish.
The government says the containers have caused port congestion and are a hazard to public health.
Some remain in storage at the Manila port while others have been disposed of in a large landfill site.
In 2016, a court in the Philippines ordered the waste to be shipped back to Canada at the expense of the importer.
That same year, Canada amended its own regulations around hazardous waste shipments to prevent a repeat of this situation.