Prime Minister Stephen Harper confirmed the decision on Wednesday with Foreign Affairs Minister John Baird bound for New York to cast Ottawa's vote and register Canada's disappointment with the latest Palestinian move at the UN for recognition.
The Harper government's support of its close friend Israel was unbowed by reports that its trusted international ally, Britain, had offered to abstain from the vote in return for a pledge from the Palestinian Authority to return to the negotiating table with the Israelis.
Asked Wednesday during a rare press conference, this time to mark the visit of the incoming Mexican president, Harper brushed aside all talk of the British move, and reiterated his firm support for the Israeli line on the resumption of peace talks without preconditions.
"It's not for me to explain the British position," said Harper.
Harper said Canada favours a two-state solution in the Middle East which requires the Palestinian authority to return to the bargaining table for talks with Israel.
"That will not be accomplished, in reality, unless and until the Palestinian Authority returns to the negotiating table and is able to get a comprehensive peace agreement with Israel.
"And we will not support any other shortcuts, or any other ways of trying to arrive at that solution without such a peace agreement."
NDP foreign affairs critic Paul Dewar accused the government of taking an "unbalanced approach" that is threatening moderate Palestinians.
"That is why our allies, including the U.K., France and the U.S., are doing the hard diplomatic work of trying to restart negotiations," Dewar charged during question period.
"How is the government's threatening approach helping to encourage moderates who want to pursue the path of politics rather than the path of violence?"
Baird replied that Canada is "tremendously disappointed" with the Palestinian Authority for its statehood bid.
"It is obvious that this will affect our relationship," Baird said. "This government makes no apologies for standing with the Jewish state."
Baird said he believed the Palestinian motion would be successful "by a wide margin." But he said he would vote against it on Canada's behalf "and stand up for what we believe is right."
"The position of the government of Canada is shared by the Obama administration that has very similar views to us," he added.
The UN General Assembly resolution would raise the Palestinians' status from a UN observer to a non-member observer state.
The United States and Israel are strongly opposed to the move.
Senior U.S. officials were unsuccessful in a last-ditch attempt to persuade Palestinian President Mahmoud Abbas to drop the statehood bid.
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