Translate the following English sentence to French:
"Some Member States, for example the United Kingdom, are already planning to impose an embargo on Sierra Leonean diamonds because there is ample evidence that the trade in precious stones has been and is still being used to finance the RUF guerrillas."
Certains États membres, comme le Royaume-Uni, envisagent déjà un embargo sur les diamants en Sierra Leone car il est amplement démontré que le commerce des pierres précieuses sert et a servi à financer la guérilla du RUF.