China has expanded its ban on ivory imports to protect African elephants, the State Forestry Administration announced on Tuesday.

From March 20, 2016, to Dec. 31, 2019, the country will forbid imports of ivory and ivory products acquired before the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) took effect in 1975.

Two one-year bans launched last year will be extended to the end of 2019.

On Oct. 15 last year, China levied a one-year ban on imports of African ivory acquired as hunting trophies. It came after another one-year ban made on Feb. 26 last year, which prohibited imports of African ivory carvings acquired after CITES.

The trade and sale of ivory carvings are legal in China if the activities conform with certain regulations. Ivory may only come from two sources: items imported before the country joined CITES in 1981, and 62 tonnes of raw-ivory stock bought from four African countries in 2008, as permitted by CITES.

Raw elephant ivory and products should only be processed at designated places, sold by certain outlets and must be individually tracked. Each legal product has been cataloged and is traceable by its own unique photo ID.