Ban told reporters today that the "most effective" way is under Chapter 7 of the UN Charter. It deals with threats to international peace and security and has provisions for enforcement by military or non-military means such as sanctions.
While in principle all Security Council resolutions are legally binding, Ban said, "in reality, we need clear guidelines under Chapter 7."
The US and Russia are arguing over putting the resolution under Chapter 7.
US Mission spokeswoman Erin Pelton said the five permanent council members the US, Russia, China, Britain and France would meet later today to discuss a draft resolution.