January 18, 2012
President Obama called Prime Minister Harper to personally convey his Administration's decision on the Keystone pipeline. The President also reaffirmed the close alliance and friendship between the United States and Canada.
Barack Obama, Readout of the President's Call with Canadian Prime Minister Harper Online by Gerhard Peters and John T. Woolley, The American Presidency Project https://www.presidency.ucsb.edu/node/310116