The Indian Ocean Island has 70 out of the 200 known gem minerals and has long been known as a rich source of stones, some like its blue sapphires being much sought after in high-end niche jewellery markets.
Analysts says about 70 percent of the land mass is potentially gem bearing The statement said permits granted to the foreign companies were being withdrawn immediately to protect the local mining industry.
"Local Entrepreneurs should be strengthened if a State is to rise up" it said.
It is unclear if the 16 companies had already been mining on the island or had been preparing to set up operations.
"Sixteen foreign companies had been given gem mining licences by the previous administration, and the president in an effort to protect local miners cancelled those permits without further investigation," it said in a statement.
President Maithripala Sirisena says that the country will not sign any agreement which is deemed a threat to domestic entrepreneurs.
The President made thi