UPDATE 2-Opposition party urges Canada to reject CNOOC's Nexen bid

* NDP cites lack of transparency in approval process

* Says deal raises alarming number of unanswered questions

* Sustainable development can't be sacrificed

* Says Canada must be strategic in development of resource

(Adds broader concerns about oil sands development, paragraphs 5-7)

OTTAWA, Oct 4 (Reuters) - The Canadian government must reject Chinese state-owned CNOOC Ltd's $15.1 billion bid for oil producer Nexen Inc until the impact of the deal on jobs and the environment is made clear, the main opposition New Democratic Party (NDP) said on Thursday.

"The lack of transparency in the approval process and an alarming number of unanswered questions, have pushed the NDP to reject, as currently structured, the transaction that would allow the state-owned CNOOC to take over the Canadian company Nexen," the left-leaning party said in a statement.

The NDP cannot force the hand of the Conservative government, which has a majority in Parliament, but Prime Minister Stephen Harper has said he will take public opinion into account as his government decides whether to approve the bid.

The NDP statement said the transaction raises many questions, including whether CNOOC will protect jobs and keep Nexen's head office in Canada. "It is also unclear how Canada's environmental standards will be enforced with regards to the sustainable development of its resources," it said.

In a news conference, the NDP made it clear its opposition was not only based on the deal itself but on broader concerns about the pace of development in northern Alberta's oil sands, one of the world's biggest crude oil deposits, where Nexen has a relatively small stake.

"We have to be strategic. The resources are going to be there," NDP industry spokeswoman Helene LeBlanc told reporters. "They're not going away, and I think we can be strategic...(on) the rate of development of the natural resource."

She said that NDP opposition was also based on the process for evaluating the bid as well as "our concerns about the company itself".

In the written statement, NDP natural resources critic Peter Julian said: "The Conservatives failed to act in good faith and inform the public of the consequences of this takeover. We're talking about a company that plays a key role in a critical sector of our economy."

The Conservative-dominated House of Commons rejected an NDP motion on Wednesday that demanded public consultations on the CNOOC deal. The vote was 145 against the motion to 125 for it.

(Reporting by David Ljunggren, Randall Palmer and Louise Egan; Editing by Peter Galloway)

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