Nancy Pelosi Says She's Concerned About Fast-Track Bill's Time Frame

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WASHINGTON, May 14 (Reuters) - U.S. House of Representatives Democratic leader Nancy Pelosi said on Thursday she had concerns over the duration of a bill in Congress to give President Barack Obama "fast-track" authority to negotiate trade deals.

The bill would let Congress vote to approve or reject trade deals but not change individual provisions. It would authorize this power for three years, with a three-year extension possible.

Of the six-year time frame that would be given to Obama and his successor, Pelosi told reporters: "This is really effectively a six year...carte blanche for fast track."

Pelosi added that the fast-track authority could apply to unknown trade deals in the future "and I would hope there could be some addressing of the length of time."

She did not say whether the White House was interested in paring back the duration of the proposed authority.

(Reporting by Richard Cowan; Writing by Emily Stephenson; Editing by Will Dunham and Lisa Lambert)