Taiwan has given the Philippines 72 hours to apologise for the death of a Taiwanese fisherman whose vessel was fired on by the Philippine coastguard.
Taipei says the incident is brutal and outrageous but Manila says the firing was in self defence.
Fisherman Hung Shih-cheng, 65, was shot dead on Thursday when the coastguard vessel opened fire on his boat.
The BBC reports he was in waters south-east of Taiwan and north of the Philippines, an area considered by both countries to be their exclusive economic zone.
The president's office and foreign ministry in Taiwan asked for a formal apology, the speeding up of the investigation into his death, punishment of the perpetrators, the payment of compensation to the fisherman's family and talks over fishing rights in the disputed area.
Taiwan also threatened to send the Philippines' representative back to Manila if its neighbour does not respond within 72 hours.
Officials in Manila have said that their initial findings suggest that the coast guard acted in self-defence and that the fishing boat tried to ram into the coastguard vessel.
The three surviving fishermen on board the vessel, including Mr Hung's son and son-in-law, have disputed this account.
After inspecting the boat, Taiwanese officials also said they did not find this explanation credible as there were 52 bullet holes in the boat and the fishermen were unarmed.