China has denied it is increasing combat readiness in response to a tense territorial row with the Philippines in the South China Sea which has dragged on for more than a month.
The stand-off erupted last month after Philippine authorities detected Chinese ships fishing near the Scarborough Shoal.
They tried to arrest the crew, but were blocked by Chinese surveillance vessels deployed to the tiny rocky outcrop in the South China Sea about 230 kilometres (140 miles) from the Philippines' main island of Luzon.
The two nations have stationed non-military vessels at the shoal since April 8 in an effort to assert their sovereignty over the area.
But China's defence ministry denied military units were getting ready for war, despite warnings in state media that China is prepared to fight to end the stand-off.
"Reports that the Guangzhou military region, the South China Sea fleet and other units have entered a state of war preparedness are untrue," the ministry said in a brief statement on its website late Friday.
The Guangzhou military region in southern China has responsibility for the area.
It gave no source for the reports, but rumours on Chinese microblogs say China has ordered some military units up to level two of its four-level scale of war preparedness, one notch from the top which indicates full readiness.
China claims virtually all of the South China Sea, which is believed to sit atop huge oil and gas reserves, as its historical territory, even waters close to the coasts of other Asian countries.
The Philippines says the shoal is part of its territory because it falls within its exclusive economic zone.
On Friday, around 300 protestors demonstrated outside the Chinese embassy in the Philippines to denounce "bullying" by Beijing.
Chinese citizens responded by holding far smaller protests outside the Philippine embassy in Beijing on Friday and Saturday, but police have not allowed sustained demonstrations.
China worries protests could spark wider social unrest.
On Saturday, police hustled away a group of five people attempting to unfurl a banner outside the embassy, who were put in a van and then driven away, an AFP photographer witnessed.
One briefly held up a sign reading: "Philippine servants, get away from Huangyan Island" using the Chinese name for the Scarborough Shoal.
A Chinese state-backed newspaper on Saturday accused the Philippines of whipping up nationalism, but it added military conflict in the South China Sea was possible.
"Nationalism seems to echo just as strongly wherever you go around the South China Sea. The Philippines is showing prominent such behaviour," the Global Times said in an editorial.
"It remains possible that military conflicts will ensue in the South China Sea, and when that happens China will certainly take firm action," it added.
Taiwan, Brunei, Vietnam and Malaysia also claim parts of the sea. The rival claims have for decades made the waters one of Asia's potential military flashpoints.
The official Xinhua news agency late Friday urged the Philippines to negotiate a diplomatic solution to the dispute.
"The Philippine government is urged to use its vision and wisdom to handle the... dispute by peaceful diplomatic means to prevent harming bilateral relations in the long run," it said.
Chinese authorities have ordered tour operators to suspend trips to the Philippines, and a Philippine official said Saturday that Chinese customs had impounded fruit imported from the Philippines, alleging pests, amid the dispute.