Harry Winston has decided not to accept gemstones from Myanmar amid criticisms of the country’s ethical standards.

The announcement came days before nonprofit Global Witness released a report alleging widespread human-rights abuses in the southeast Asian nation, also known as Burma.

A military junta took over Myanmar in February, prompting the US to place sanctions on its key gemstone companies. The country is best known for its jade and rubies, which the industry considers to be some of the best in the world.

Previously, the jeweler, a unit of Swatch Group, sourced gemstones from “trusted and verified” suppliers who had certified that their Burmese rubies and jade were imported during a period without international sanctions, according to its website. The company also took measures to verify the importation dates and the origin documentation to check that everything complied with the rules, it added. It did not buy directly from the country.