"The United Nations Security Council should urgently impose a global arms embargo on Myanmar in response to the military coup and to deter the junta from committing further abuses," the letter said.

It went on to say, "Governments that permit arms transfers to Myanmar -- including China, India, Israel, North Korea, the Philippines, Russia, and Ukraine -- should immediately stop the supply of any weapons, munitions, and related equipment."

Three of the named countries are currently members of the Security Council: permanent members China and Russia -- who both hold veto power in the body -- and non-permanent member India.

"Given the mass atrocities against the Rohingya, decades of war crimes, and the overthrow of the elected government, the least the UN Security Council can do is impose a global arms embargo on Myanmar," Human Rights Watch (HRW) director Kenneth Roth wrote.

"The Security Council should also impose targeted sanctions, global travel bans, and asset freezes on the leadership of the junta and military-owned conglomerates," said the signatories, which also included dozens of Asian NGOs.