UPDATE 1-Obama notes concerns over "dirty" Keystone oil extraction
March 06, 2015 at 17:12 PM EST
COLUMBIA, S.C., March 6 (Reuters) - U.S. President Barack Obama amplified the concerns of environmentalists about the Keystone XL oil pipeline on Friday and repeated his own reservations the project would have few benefits, but said he has not made a decision on the project.
