Vietnam has agreed to rescue more than 1,000 bears from illegal farms across the country, in a move to end the traditional medicine trade of harvesting their bile.

Vietnam's Administration of Forestry (VNFOREST) and non-profit group Animals Asia signed an agreement Wednesday to rescue all remaining bears from farms, committing to end bile trade and close all facilities within five years.

Though bear bile farming has been outlawed in Vietnam since 1992, many bile farms use a legal loophole allowing them to raise the animals as pets. Bears are still captured and caged in illicit facilities where their bile is extracted using invasive and painful techniques.

There are currently about 1,200 bears in captivity in the country, down from more than 4,000 in 2005, caged in more than 400 bear farms across the country. 

Animals Asia estimates it will cost up to 20 million US dollars to rescue and build enough sanctuaries to house the bears, and it called on donors, companies and the government to pitch in.

Officials said funding is the main hurdle to rescuing the bears and putting an end to the trade. 

Tuan Bendixsen, Vietnam director for Animals Asia, warned that bile farms could move into neighboring Laos or Cambodia, and urged countries to adhere to an international convention that bans cross-border bear and bile trading. 

The bears are often kept in small cages, and their bile is "free dripped" via a hole in the animal's gall bladder or a catheter. Many are starved, dehydrated, wounded and psychologically scarred when they are rescued.

Bear bile contains an acid which can help treat liver and gall bladder illnesses, though effective herbal alternatives are available.

Wednesday's agreement follows an announcement in 2015 from Vietnam's Traditional Medicine Association to remove bear bile from its list of sanctioned prescriptions by 2020.