Pope Francis appeared to back Native Americans seeking to halt part of the Dakota Access Pipeline, saying indigenous cultures have a right to defend “their ancestral relationship to the earth”.

The Argentinian pontiff, who has often strongly defended indigenous rights since his election in 2013, made his comments on protection of native lands to representative of tribes attending the Indigenous Peoples Forum in Rome.

While he did not name the pipeline, he used strong and clear language applicable to the conflict, saying development had to be reconciled with “the protection of the particular characteristics of indigenous peoples and their territories”.

Sioux from Standing Rock claim victory over Dakota Pipeline Show all 21 1 /21 Sioux from Standing Rock claim victory over Dakota Pipeline Sioux from Standing Rock claim victory over Dakota Pipeline CANNON BALL, ND - DECEMBER 05: Despite blizzard conditions, military veterans march in support of the "water protectors" at Oceti Sakowin Camp on the edge of the Standing Rock Sioux Reservation on December 5, 2016 outside Cannon Ball, North Dakota. Over the weekend a large group of military veterans joined native Americans and activists from around the country who have been at the camp for several months trying to halt the construction of the Dakota Access Pipeline. Yesterday the US Army Corps of Engineers announced that it will not grant an easement for the pipeline to cross under a lake on the Sioux Tribes Standing Rock reservation. The proposed 1,172-mile-long pipeline would transport oil from the North Dakota Bakken region through South Dakota, Iowa and into Illinois. (Photo by Scott Olson/Getty Images) Getty Images Sioux from Standing Rock claim victory over Dakota Pipeline CANNON BALL, ND - DECEMBER 04: Fireworks fill the night sky above Oceti Sakowin Camp as activists celebrate after learning an easement had been denied for the Dakota Access Pipeline near the edge of the Standing Rock Sioux Reservation on December 4, 2016 outside Cannon Ball, North Dakota. The US Army Corps of Engineers announced today that it will not grant an easement to the Dakota Access Pipeline to cross under a lake on the Sioux Tribes Standing Rock reservation, ending a months-long standoff. (Photo by Scott Olson/Getty Images) Getty Images Sioux from Standing Rock claim victory over Dakota Pipeline CANNON BALL, ND - DECEMBER 05: Despite blizzard conditions, military veterans march in support of the "water protectors" at Oceti Sakowin Camp on the edge of the Standing Rock Sioux Reservation on December 5, 2016 outside Cannon Ball, North Dakota. Over the weekend a large group of military veterans joined native Americans and activists from around the country who have been at the camp for several months trying to halt the construction of the Dakota Access Pipeline. Yesterday the US Army Corps of Engineers announced that it will not grant an easement for the pipeline to cross under a lake on the Sioux Tribes Standing Rock reservation. The proposed 1,172-mile-long pipeline would transport oil from the North Dakota Bakken region through South Dakota, Iowa and into Illinois. (Photo by Scott Olson/Getty Images) Getty Images Sioux from Standing Rock claim victory over Dakota Pipeline CANNON BALL, ND - DECEMBER 04: Fireworks fill the night sky above Oceti Sakowin Camp as activists celebrate after learning an easement had been denied for the Dakota Access Pipeline near the edge of the Standing Rock Sioux Reservation on December 4, 2016 outside Cannon Ball, North Dakota. The US Army Corps of Engineers announced today that it will not grant an easement to the Dakota Access Pipeline to cross under a lake on the Sioux Tribes Standing Rock reservation, ending a months-long standoff. (Photo by Scott Olson/Getty Images) Getty Images Sioux from Standing Rock claim victory over Dakota Pipeline CANNON BALL, ND - DECEMBER 05: Despite blizzard conditions, military veterans march in support of the "water protectors" at Oceti Sakowin Camp on the edge of the Standing Rock Sioux Reservation on December 5, 2016 outside Cannon Ball, North Dakota. Over the weekend a large group of military veterans joined native Americans and activists from around the country who have been at the camp for several months trying to halt the construction of the Dakota Access Pipeline. Yesterday the US Army Corps of Engineers announced that it will not grant an easement for the pipeline to cross under a lake on the Sioux Tribes Standing Rock reservation. The proposed 1,172-mile-long pipeline would transport oil from the North Dakota Bakken region through South Dakota, Iowa and into Illinois. (Photo by Scott Olson/Getty Images) Getty Images Sioux from Standing Rock claim victory over Dakota Pipeline CANNON BALL, ND - DECEMBER 04: Native American and other activists celebrate after learning an easement had been denied for the Dakota Access Pipeline at Oceti Sakowin Camp on the edge of the Standing Rock Sioux Reservation on December 4, 2016 outside Cannon Ball, North Dakota. The US Army Corps of Engineers announced today that it will not grant an easement to the Dakota Access Pipeline to cross under a lake on the Sioux Tribes Standing Rock reservation, ending a months-long standoff. (Photo by Scott Olson/Getty Images) Getty Sioux from Standing Rock claim victory over Dakota Pipeline CANNON BALL, ND - DECEMBER 04: Chief Arvol Looking Horse of the Lakota/Dakota/Nakota Nation listens to speakers during an interfaith ceremony at Oceti Sakowin Camp on the edge of the Standing Rock Sioux Reservation on December 4, 2016 outside Cannon Ball, North Dakota. Native Americans and activists from around the country have been gathering at the camp for several months trying to halt the construction of the Dakota Access Pipeline. Today the US Army Corps of Engineers announced that it will not grant an easement for the pipeline to cross under a lake on the Sioux Tribes Standing Rock reservation, ending the months-long standoff. The proposed 1,172-mile-long pipeline would transport oil from the North Dakota Bakken region through South Dakota, Iowa and into Illinois. (Photo by Scott Olson/Getty Images) Getty Images Sioux from Standing Rock claim victory over Dakota Pipeline CANNON BALL, ND - DECEMBER 04: An Native American activist rides down fom a ridge which overlooks Oceti Sakowin Camp on the edge of the Standing Rock Sioux Reservation on December 4, 2016 outside Cannon Ball, North Dakota. Native Americans and activists from around the country have been gathering at the camp for several months trying to halt the construction of the Dakota Access Pipeline. The proposed 1,172-mile-long pipeline would transport oil from the North Dakota Bakken region through South Dakota, Iowa and into Illinois. (Photo by Scott Olson/Getty Images) Getty Images Sioux from Standing Rock claim victory over Dakota Pipeline CANNON BALL, ND - DECEMBER 05: Despite blizzard conditions, military veterans march in support of the "water protectors" at Oceti Sakowin Camp on the edge of the Standing Rock Sioux Reservation on December 5, 2016 outside Cannon Ball, North Dakota. Over the weekend a large group of military veterans joined native Americans and activists from around the country who have been at the camp for several months trying to halt the construction of the Dakota Access Pipeline. Yesterday the US Army Corps of Engineers announced that it will not grant an easement for the pipeline to cross under a lake on the Sioux Tribes Standing Rock reservation. The proposed 1,172-mile-long pipeline would transport oil from the North Dakota Bakken region through South Dakota, Iowa and into Illinois. (Photo by Scott Olson/Getty Images) Getty Images Sioux from Standing Rock claim victory over Dakota Pipeline CANNON BALL, ND - DECEMBER 04: Political activist Cornel West listen to speakers during an interfaith ceremony at Oceti Sakowin Camp on the edge of the Standing Rock Sioux Reservation on December 4, 2016 outside Cannon Ball, North Dakota. Native Americans and activists from around the country have been gathering at the camp for several months trying to halt the construction of the Dakota Access Pipeline. Today the US Army Corps of Engineers announced that it will not grant an easement for the pipeline to cross under a lake on the Sioux Tribes Standing Rock reservation, ending the months-long standoff. The proposed 1,172-mile-long pipeline would transport oil from the North Dakota Bakken region through South Dakota, Iowa and into Illinois. (Photo by Scott Olson/Getty Images) Getty Images Sioux from Standing Rock claim victory over Dakota Pipeline Activists hold hands during a prayer circle as they try to surround the entire camp at Oceti Sakowin Camp on the edge of the Standing Rock Sioux Reservation on December 4, 2016 outside Cannon Ball, North Dakota. Native Americans and activists from around the country gather at the camp trying to halt the construction of the Dakota Access Pipeline. / AFP / JIM WATSON (Photo credit should read JIM WATSON/AFP/Getty Images) AFP/Getty Images Sioux from Standing Rock claim victory over Dakota Pipeline Activists celebrate at Oceti Sakowin Camp on the edge of the Standing Rock Sioux Reservation on December 4, 2016 outside Cannon Ball, North Dakota, after hearing that the Army Corps of Engineers has denied the current route for the Dakota Access pipeline. / AFP / JIM WATSON (Photo credit should read JIM WATSON/AFP/Getty Images) AFP/Getty Images Sioux from Standing Rock claim victory over Dakota Pipeline CANNON BALL, ND - DECEMBER 04: Chief Arvol Looking Horse (L) of the Lakota/Dakota/Nakota Nation listens as political activist Cornel West speaks during an interfaith ceremony at Oceti Sakowin Camp on the edge of the Standing Rock Sioux Reservation on December 4, 2016 outside Cannon Ball, North Dakota. Native Americans and activists from around the country have been gathering at the camp for several months trying to halt the construction of the Dakota Access Pipeline. Today the US Army Corps of Engineers announced that it will not grant an easement for the pipeline to cross under a lake on the Sioux Tribes Standing Rock reservation, ending the months-long standoff. The proposed 1,172-mile-long pipeline would transport oil from the North Dakota Bakken region through South Dakota, Iowa and into Illinois. (Photo by Scott Olson/Getty Images) Getty Images Sioux from Standing Rock claim victory over Dakota Pipeline CANNON BALL, ND - DECEMBER 05: Military veterans from Southern California collect firewood for their campsite at Oceti Sakowin Camp on the edge of the Standing Rock Sioux Reservation on December 5, 2016 outside Cannon Ball, North Dakota. Over the weekend a large group of military veterans joined native Americans and activists from around the country who have been at the camp for several months trying to halt the construction of the Dakota Access Pipeline. Yesterday the US Army Corps of Engineers announced that it will not grant an easement for the pipeline to cross under a lake on the Sioux Tribes Standing Rock reservation. The proposed 1,172-mile-long pipeline would transport oil from the North Dakota Bakken region through South Dakota, Iowa and into Illinois. (Photo by Scott Olson/Getty Images) Getty Images Sioux from Standing Rock claim victory over Dakota Pipeline CANNON BALL, ND - DECEMBER 05: Despite blizzard conditions, military veterans march in support of the "water protectors" at Oceti Sakowin Camp on the edge of the Standing Rock Sioux Reservation on December 5, 2016 outside Cannon Ball, North Dakota. Over the weekend a large group of military veterans joined native Americans and activists from around the country who have been at the camp for several months trying to halt the construction of the Dakota Access Pipeline. Yesterday the US Army Corps of Engineers announced that it will not grant an easement for the pipeline to cross under a lake on the Sioux Tribes Standing Rock reservation. The proposed 1,172-mile-long pipeline would transport oil from the North Dakota Bakken region through South Dakota, Iowa and into Illinois. (Photo by Scott Olson/Getty Images) Getty Images Sioux from Standing Rock claim victory over Dakota Pipeline CANNON BALL, ND - DECEMBER 03: Activists participate in an art project conceived by Cannupa Hunska Luger, from the Standing Rock Sioux Tribe, at Oceti Sakowin Camp on the edge of the Standing Rock Sioux Reservation on December 3, 2016 outside Cannon Ball, North Dakota. Native Americans and activists from around the country have been gathering at the camp for several months trying to halt the construction of the Dakota Access Pipeline. The proposed 1,172-mile-long pipeline would transport oil from the North Dakota Bakken region through South Dakota, Iowa and into Illinois. (Photo by Scott Olson/Getty Images) Getty Images Sioux from Standing Rock claim victory over Dakota Pipeline CANNON BALL, ND - DECEMBER 05: Military veterans are briefed on cold-weather safety issues and their overall role at Oceti Sakowin Camp on the edge of the Standing Rock Sioux Reservation on December 5, 2016 outside Cannon Ball, North Dakota. Over the weekend a large group of military veterans joined native Americans and activists from around the country who have been at the camp for several months trying to halt the construction of the Dakota Access Pipeline. Yesterday the US Army Corps of Engineers announced that it will not grant an easement for the pipeline to cross under a lake on the Sioux Tribes Standing Rock reservation. The proposed 1,172-mile-long pipeline would transport oil from the North Dakota Bakken region through South Dakota, Iowa and into Illinois. (Photo by Scott Olson/Getty Images) Getty Images Sioux from Standing Rock claim victory over Dakota Pipeline CANNON BALL, ND - DECEMBER 04: Native American and other activists celebrate after learning an easement had been denied for the Dakota Access Pipeline at Oceti Sakowin Camp on the edge of the Standing Rock Sioux Reservation on December 4, 2016 outside Cannon Ball, North Dakota. The US Army Corps of Engineers announced today that it will not grant an easement to the Dakota Access Pipeline to cross under a lake on the Sioux Tribes Standing Rock reservation, ending a months-long standoff. (Photo by Scott Olson/Getty Images) Getty Images Sioux from Standing Rock claim victory over Dakota Pipeline CANNON BALL, ND - DECEMBER 04: Native American activists celebrate after learning an easement had been denied for the Dakota Access Pipeline at Oceti Sakowin Camp on the edge of the Standing Rock Sioux Reservation on December 4, 2016 outside Cannon Ball, North Dakota. The US Army Corps of Engineers announced today that it will not grant an easement to the Dakota Access Pipeline to cross under a lake on the Sioux Tribes Standing Rock reservation, ending a months-long standoff. (Photo by Scott Olson/Getty Images) Getty Images Sioux from Standing Rock claim victory over Dakota Pipeline CANNON BALL, ND - DECEMBER 04: Native American and other activists celebrate after learning an easement had been denied for the Dakota Access Pipeline at Oceti Sakowin Camp on the edge of the Standing Rock Sioux Reservation on December 4, 2016 outside Cannon Ball, North Dakota. The US Army Corps of Engineers announced today that it will not grant an easement to the Dakota Access Pipeline to cross under a lake on the Sioux Tribes Standing Rock reservation, ending a months-long standoff. (Photo by Scott Olson/Getty Images) Getty Images Sioux from Standing Rock claim victory over Dakota Pipeline Activists celebrate at Oceti Sakowin Camp on the edge of the Standing Rock Sioux Reservation on December 4, 2016 outside Cannon Ball, North Dakota, after hearing that the Army Corps of Engineers has denied the current route for the Dakota Access pipeline. The US Army Corps of Engineers on Sunday announced they will no longer allow the Dakota Access Pipeline to cross under a lake on the Standing Rock reservation in North Dakota, marking a huge win for Native Americans and protesters who had long opposed the construction. / AFP / JIM WATSON (Photo credit should read JIM WATSON/AFP/Getty Images) AFP/Getty Images

His comments came within days of a US federal judge denying a request by tribes to halt construction of the final link of the project that sparked months of protests by activists aimed at stopping the 1,170-mile line.

The tribe and its supporters believe the pipeline poses a threat to a reservoir that supplies the tribe's drinking water. The pipeline project, which crosses four states, is estimated to be able to transport 570,000 barrels of oil a day.

Speaking in Spanish, Pope Francis said the need to protect native territories was “especially clear when planning economic activities which may interfere with indigenous cultures and their ancestral relationship to the earth”.

The Standing Rock Sioux and Cheyenne River Sioux tribes have argued the project would prevent them from practising religious ceremonies at a lake they say is surrounded by sacred ground.

“In this regard, the right to prior and informed consent (of native peoples) should always prevail,” the pope said, citing the 1997 UN Declaration on the Rights of Indigenous Peoples.

Thousands of tribe members, environmentalists and others set up camps last year on Army Corps land in the North Dakota plains as protests intensified.

In December, the administration of former US President Barack Obama denied the last permit needed by Energy Transfer Partners, which is building the $3.8 billion (£3.05 billion) pipeline.

But last week, the US Army Corps of Engineers granted a final easement, after President Donald Trump issued an order to advance the project days after he took office in January.

The pope made an indirect criticism last week of another Trump project, a wall along the border with Mexico, saying society should not create “walls but bridges” and ask others to pay for them.

Pope Francis, who wrote a major encyclical letter in 2015 on climate change and the environment, told the group that new technologies could be legitimate but had to respect the earth.