Erakat's remarks came after several European parliaments pressed their governments to recognise full Palestinian statehood, and as prospects for a resumption of peace talks with Israel looked bleak.
"We are at the (UN) Security Council now, today. We are continuing our consultation. We want a Security Council resolution that will preserve the two-state solution," Erakat told foreign journalists gathered near the West Bank city of Bethlehem.
"We want a specific time frame to end the occupation.
"We're being helped a great deal in the Security Council by many nations," he added, referring to recent votes of British, French and Spanish MPs in favour of recognising Palestine as a state.
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"We are hoping to achieve this resolution before the end of the month, before Christmas as a matter of fact."
The Palestinians have been pressing Security Council members to adopt a resolution giving a timeframe -- two years -- for the withdrawal of Israel from occupied Palestinian territory.
The United States has reiterated its opposition to what it sees as unilateral Palestinian measures that bypass peace talks with Israel.
But talks do not look set to resume, having collapsed in a round of recriminations in April despite a concerted diplomatic drive by US Secretary of State John Kerry.
Erakat said the Palestinians hoped the US would not veto the resolution, but that if it did, "president (Mahmud) Abbas will be signing immediately 22 conventions," ensuring Palestinian membership of the International Criminal Court, through which it has threatened to sue Israel for alleged war crimes.