Hanoi, Vietnam ? Two of the countries hardest hit by bird flu announced extreme measures to fight the disease Tuesday, with China promising to vaccinate its entire poultry stock of 14 billion birds and Vietnam launching a campaign to purge its two largest cities of poultry.

Jia Youling, chief veterinary officer in China’s Agriculture Ministry, said China is in the process of vaccinating all poultry in the country. He said the government will pay all fees involved, but he did not provide any details of how officials would carry out the vaccinations.

China has more than 14 billion farm poultry, accounting for nearly 21 percent of the world’s total. Millions of birds have already been vaccinated in the country because of previous outbreaks.

Meanwhile, in Vietnam, government officials in Ho Chi Minh City and the capital Hanoi have warned farmers to kill or sell all poultry by Monday. They will be compensated at half the current market value if they act now, but birds found alive after the deadline will be destroyed with no compensation, officials said.

The campaign is one of the most extreme measures taken in the communist country to try to slow the H5N1 virus.