First Nations leaders line up to sign the Treaty Alliance Against Tar Sands Expansion during an announcement on oil sands pipelines, with special relevance for the Kinder Morgan and Northern Gateway proposals, at the Musqueam Community Centre in Vancouver, British Columbia, Canada, September 22, 2016. REUTERS/Ben Nelms

Protesters demonstrate against the Energy Transfer Partners' Dakota Access oil pipeline near the Standing Rock Sioux reservation, in Los Angeles, California, September 13, 2016. REUTERS/Lucy Nicholson

Manuel Domingos Vicente, Vice-President of Angola, addresses the 71st session of the United Nations General Assembly at the UN headquarters in New York on September 22, 2016. / AFP PHOTO / DOMINICK REUTERDOMINICK REUTER/AFP/Getty Images

Russian Finance Minister Anton Siluanov speaks during a news conference in Moscow, Russia September 12, 2016. REUTERS/Maxim Zmeyev

Officer Betty Shelby of the City of Tulsa Police Department in Tulsa, Oklahoma is shown in this undated photo provided September 21, 2016. Photo courtesy of City of Tulsa Police Dept/Handout via REUTERS

T-shirts with the image of Martin Luther King and with the words "I can't breathe" are pictured for sale during a Martin Luther King day rally in the Harlem section of New York January 19, 2015. REUTERS/Carlo Allegri

Gabriel George of the Tsleil-Waututh Nation is pictured during the signing of the Treaty Alliance Against Tar Sands Expansion during an announcement on oil sands pipelines, with special relevance for the Kinder Morgan and Northern Gateway proposals, at the Musqueam Community Centre in Vancouver, British Columbia, Canada, September 22, 2016. REUTERS/Ben Nelms

A First Nations signs the Treaty Alliance Against Tar Sands Expansion with other First Nations leaders during an announcement on oil sands pipelines, with special relevance for the Kinder Morgan and Northern Gateway proposals, at the Musqueam Community Centre in Vancouver, British Columbia, Canada, September 22, 2016. REUTERS/Ben Nelms