Perfecto Yasay Jr said they did not seek China's permission as it would mean acceptance of their authority.
Like Philippines President Duterte, Najib too seeks closer ties with China.
The government is also planning to approve a bill that would reintroduce capital punishment for major crimes.
Meanwhile, the White House has signalled it is open to an Obama-Duterte meet during the Apec summit in November.
The couple said they were the directors of Street Kids Philippine Mission that has been operating for six years.
Jeremy Agerico Rosario said fishermen have suffered badly due to denial of access to Panatag.
Tokyo has been concerned about Duterte's plans to sever relations with US and strengthen ties with China.
Duterte, however, said that he will no longer follow a foreign policy that is influenced by the US.
Health services have been struggling to accommodate the thousands of pushers who are in need of help.
President Rodrigo Duterte announced in Beijing that he would end military and economic ties with the US.
The two nations have signed 13 trade deals during Duterte's four-day visit to China.
The president said the country would instead strengthen ties with China and Russia.
Haima is the strongest cyclone to hit the Southeast Asian region in three years.
Philippines President Rodrigo Duterte said his foreign policy will now veer towards China.
Seeking closer ties, Philippines President Rodrigo Duterte is on a 4-day visit to China from 18 to 21 October.
The Philippines is ready to cooperate with Beijing to help build its economy, Duterte said.
The Philippines president will be accompanied by a 400-strong business delegation to China on his three-day visit.
Drug use is often a symptom of social problems, not the cause. Where there is demand, there will be supply.
Justice Antonio Carpio said giving up sovereign rights would amount to violation of the Constitution.
'I am very sure they cannot be brighter than me,' the president said.
Neither the motive behind the killings nor the identities of the suspects are known yet.
Duterte said the third and final list has names of about 5,000 policemen, in addition to judges and governors.