The UN Security Council hit deadlock Monday on a statement on the Gaza conflict with the United States saying it opposes any action that undermines efforts to reach a ceasefire.
But Russia warned that unless an Arab-proposed statement calling for Israel-Hamas hostilities to end was agreed by Tuesday morning it would press for a vote on the full council resolution -- setting up a potential veto clash with the United States.
The United States, Britain, France and Germany all had problems with a text proposed by Arab nations last Thursday because it made no mention of rocket fire from Palestinian militants in Gaza, diplomats said.
All the western nations have said that Israel has the right to defend itself, while the Europeans have urged restraint on the Israeli government in its latest offensive on Gaza which has now left more than 100 dead.
Palestinian envoy to the UN, Riyad Mansour, highlighted the growing frustration of the Palestinian Authority and its allies as the fighting intensifies and the council says nothing.
The Security Council cannot "remain on the margin," he told reporters. He said it was now urgent for the "the Security Council to shoulder its responsibility and stop this aggression against our people."
US ambassador Susan Rice said there had to be an agreed ceasefire between the Israelis and Hamas for any halt in violence to be "meaningful or sustainable."
"The United States and countries in the region are working energetically through all diplomatic channels to try to negotiate an end to the violence, a de-escalation," Rice told reporters after the talks.
She said President Barack Obama and Secretary of State Hillary Clinton have been on the telephone with Middle East leaders "throughout the day."
It was "vitally important" that any Security Council action "is reinforcing the prospects for an agreed cessation and not doing anything that could undermine that prospect or run counter to it. That is our principal objective in these discussions and we will continue to pursue that aim," she added.
The US ambassador would seek instructions from the US administration on the Arab text during the night, but she commented: Again we will judge the draft as to whether it advances the goal of supporting an agreed cessation."
Russian ambassador Vitaly Churkin said the Arab proposal, made through Morocco, is "a very good text".
"If the statement is not adopted at 9:00 am (1400 GMT) tomorrow morning we will go for a vote of our draft" on Wednesday afternoon.
Several diplomats said they expected objections to the draft text to be made by at least three Security Council members.
The Russian resolution would call for a cessation of violence, support for Egyptian-led efforts to secure a ceasefire and encourage Israel and the Palestinian Authority to resume their frozen talks, according to a copy obtained by AFP.
If the Russian resolution was put to a vote it would probably be vetoed by the United States, which systematically blocks resolutions seen to be critical of Israel.