UPDATE 2-Obama aide quits over Clinton 'monster' comment

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By Caren Bohan

CHICAGO, March 7 (Reuters) - A foreign policy adviser to Democratic presidential candidate Barack Obama resigned on Friday after calling campaign rival Hillary Clinton a "monster" during an interview with a British newspaper.

Samantha Power, a foreign policy aide on the Illinois senator's White House campaign, said the comments were inexcusable. They were published on Friday by The Scotsman newspaper.

"With deep regret, I am resigning from my role as an adviser to the Obama campaign effective today," Power said in a statement.

"Last Monday, I made inexcusable remarks that are at marked variance from my oft-stated admiration for Senator Clinton and from the spirit, tenor and purpose of the Obama campaign."

The comment threatened to be an embarrassment for Obama, who has criticized Clinton for what he called her negative campaign tactics and has stressed his commitment to rising above political bickering.

Obama, an Illinois senator, and Clinton, a New York senator, are locked in a drawn-out battle for the Democratic nomination to face Republican John McCain in November's presidential election.

Power's comments were made on Monday before Clinton revived her presidential bid with wins in the big states of Ohio and Texas.