A floating dead pig infected with African swine fever washed up in Taiwan last week, according to a UN report, which also recorded a fresh mainland China outbreak and an attempt to illegally transport infected pigs.

China's swine herd has been devastated by the outbreak of the disease, first reported by the government in August last year.

An update on the crisis from the Food and Agriculture Organization (FAO) of the United Nations dated Thursday said the dead pig was found floating on November 6 near Taiwan's Xiaojinmen Island -- also known as Lieyu -- close to the mainland province of Fujian.

It said the pig tested positive for the same strain of swine fever that has unleashed havoc in mainland China.

The FAO said this is the first floating dead pig reported since June, and pointed out that the last reported outbreak in Fujian was last December.

The report also documented that a vehicle illegally transporting infected piglets across provinces was intercepted earlier in November on an expressway in the southwestern municipality of Chongqing.

There was also a fresh outbreak in China's southwestern Yunnan province this month, the FAO said, totalling 163 outbreaks in 32 provinces and regions.

Beijing has been battling to get a grip on the crisis, which has sent pork prices soaring.

Around one million pigs have been killed since the first outbreak of swine fever last August, according to official statistics, but that is widely considered to be an underestimate.

One pig farmer told AFP last month that some affected farmers were quietly selling or disposing of dead pigs rather than declaring them to the government.

A Rabobank report has warned China could lose 200 million pigs during the epidemic.

Prices of pork -- which is the staple meat in China -- have more than doubled in the past year, according to China's National Bureau of Statistics.

Data last week showed China's consumer prices grew at their fastest rate in almost eight years in October, driven by a spike in pork prices.

China's top economic planner said on Friday it will release frozen pork reserves to the market at "an appropriate time".

Beijing will also step up efforts to boost hog production through central budget support, Meng Wei of the National Development and Reform Commission said, according to state news agency Xinhua.

The UN has also documented cases of swine fever in neighbouring Asian countries, including three new cases among wild pigs in South Korea.