A pledge by Hong Kong to ban its ivory trade has been welcomed by conservationists who describe it as a key step toward curbing the slaughter of African elephants.

Hong Kong's leader, Leung Chun-ying, said Wednesday that the semiautonomous Chinese city will take legislative steps as soon as possible to completely ban the sale of ivory.

Peter Knights, executive director of San Francisco-based WildAid, has congratulated Hong Kong for its announcement. His organization has cited reports that most of the ivory sold in Hong Kong was being smuggled to the Chinese mainland.

China is the world's largest market for illegal ivory, which has been thriving under the cover of legal ivory sales. In September, the United States and China agreed to implement nearly complete bans on the ivory trade.