US President Donald Trump will approve two controversial oil pipelines by executive order Tuesday, US media reported.

He is expected to okay the Keystone XL pipeline -- which would carry crude from Canada to US refineries on the Gulf Coast -- and an equally controversial pipeline crossing in North Dakota, Fox News and Bloomberg reported.

Former president Barack Obama had rejected Keystone under pressure from environmental activists.

The Canadian government led by Prime Minister Justin Trudeau has cautiously supported the plan, seeing it as a means of boosting business.

But Canada's liberal leader has also helped wage the international charge against climate change.

The Dakota Access Pipeline has become more of a political hot potato in the United States.

Native Americans and their supporters strongly protested against the project, prompting the US Army Corps of engineers -- which has approval authority -- to nix the plans under the Obama administration.

Thousands had camped in freezing winter temperatures to block the oleoduct's planned route.

The Standing Rock Sioux Tribe is concerned about potential water pollution, saying the pipeline's route endangers areas with sacred historic artifacts.

The standoff -- which included some 2,000 military veterans who joined the protest -- prompted violent clashes with law enforcement as well as sympathetic demonstrations nationwide.

But Trump has supported the 1,172-mile (1,886-kilometer) oil pipeline, which would snake through four US states.