Australian Minister for Defence Peter Dutton said the ship had been tracked along the coastline for the past week and was sighted on Friday morning heading north, about 250 nautical miles from Broome in Western Australia.
Asked about the ship, Chinese Foreign Ministry spokesperson Zhao Lijian said he had no information about the specific situation, but “China always abides by international law and international practice”.
“The relevant Australian politician should see the relevant situation objectively and calmly, and not make sensational remarks,” Zhao told reporters at a daily briefing.
Dutton had said the vessel’s mission was “to collect intelligence right along the coastline”.
“It has been in close proximity to military and intelligence installations on the west coast of Australia,” he said, adding that the Australian Defence Force had been tracking the spy ship in the past “week or so”.
The Defence Minister, who described the situation as unprecedented, said he was concerned not just about how far south the ship had travelled, but also that it had “hugged” the coastline as it headed back north towards Darwin.
He dubbed the matter “very strange” and said he expected the ship was collecting as much intelligence as it could.
Australia’s already tense relationship with Beijing has been strained further recently following China signing a security pact with Solomon Islands.