UPDATE 1-CNOOC bid for Nexen raises difficult policy issues-Canada PM

* Canada studying whether to approve CNOOC bid for Nexen

* Some in Canada's ruling party uneasy about CNOOC bid

* Canada PM says U.S. won't influence final decision

(Adds quotes, background)

OTTAWA, Oct 4 (Reuters) - CNOOC Ltd's $15.1 billion bid for oil firm Nexen Inc raises a series of difficult policy questions, Canadian Prime Minister Stephen Harper said on Thursday.

Canada's Conservative government is currently deciding whether to approve the bid. Some Conservative legislators are nervous about the idea of a Chinese state-owned enterprise buying up Canadian energy patch assets.

"This particular transaction raises a range of difficult policy questions, difficult and forward-looking issues. Those things will all be taken into account," Harper told reporters in Ottawa.

Fund managers and market analysts say they expect Ottawa will ultimately approve the deal but not before attaching a series of conditions.

Asked about speculation the United States was putting pressure on Canada to scrap the deal, Harper replied: "The government of Canada will take its own decision irrespective of what the government of the United States does. We don't obviously follow their judgments in these matters."

A handful of U.S. lawmakers have asked Treasury Secretary Timothy Geithner to review the deal with one urging the panel to block the deal in order to extract trade and investment concessions from the Chinese government.

(Reporting by Randall Palmer, writing by David Ljunggren; Editing by Marguerita Choy)

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