Palestinian and Arab ambassadors want the UN Security Council to condemn Israel for killing Sheik Ahmed Yassin in a resolution the United States has said it will veto.
Sheik Yassin, the quadriplegic spiritual leader of Hamas, was targeted on Monday in an Israeli helicopter missile strike outside a mosque in Gaza. The killing has been criticised around the world as sparking an escalation of Middle East violence.
Algeria, the only Arab nation on the 15-member council, introduced a draft resolution late on Wednesday condemning "the most recent extrajudicial execution committed by Israel." It has scheduled a vote later today.
The measure also condemns "all attacks against any civilians as well as all acts of violence and destruction" in an effort to get European votes.
The United States has said it is troubled by the assassination, but it opposes the draft resolution because it does not mention Hamas as a group responsible for suicide bombings against Israeli civilians.
"If the Security Council is going to pronounce itself on this question, it must recognise the reality that Hamas has been responsible for numerous, extensive and very recent terrorist activities," US Ambassador Mr John Negroponte said.