By Valerie Volcovici

(Reuters) Former Democratic presidential candidate Bernie Sanders and four other U.S. senators have called on President Barack Obama to order a comprehensive environmental review of a pipeline project that has stirred widespread opposition from Native Americans and environmental activists.

After a federal appeals court last week denied a request to halt construction of the Dakota Access Pipeline, the senators asked Obama to direct the Army Corps of Engineers to complete a full environmental impact statement, including stronger tribal consultation, for a contested part of the route.

"The project's current permits should be suspended and all construction stopped until a complete environmental and cultural review has been completed for the entire project," said the letter by Sanders and Democratic Senators Dianne Feinstein, Ed Markey, Patrick Leahy and Benjamin Cardin.

Also last week, the governments of 19 cities, including St. Louis and Minneapolis, passed ordinances to support the Standing Rock tribe in opposition of the pipeline.

In recent weeks, protests against the Dakota Access pipeline led by the Standing Rock Sioux tribe in North Dakota have drawn international attention, prompting the U.S. government to temporarily block construction on federal land.

Tribal leaders say the pipeline will desecrate land and pollute water, especially around the planned crossing through Lake Oahe, a sacred site. Opposition to the pipeline has drawn support from 200 Native American tribes.

On Tuesday, anti-pipeline activists in four states, in solidarity with the Dakota pipeline protesters, closed pipeline valves to halt the flow of crude through arteries transporting 15 percent of U.S. oil consumption.

A day earlier, actress Shailene Woodley was arrested in North Dakota while protesting the pipeline, an incident that was live streamed on Facebook.

On Thursday, Amy Goodman, a journalist from the independent TV and radio program Democracy Now!, said she would turn herself over to authorities in North Dakota on Monday morning, in response to a criminal complaint was filed against her on Sept. 8 for trespassing.

Goodman had filmed the crackdown on protesters by authorities last month.

"I was doing my job as a journalist, covering a violent attack on Native American protesters," she said.

When fully connected, the 1,100-mile (1,770 km) pipeline would be the first to carry crude directly to the U.S. Gulf from the Bakken shale, a vast oil formation in North Dakota, Montana and parts of Canada.

The $3.7 billion project is being built by the Dakota Access subsidiary of Dallas-based Energy Transfer Partners LP, which has vowed to complete construction.

"There must be a serious consideration of the full potential climate impacts of this pipeline prior to the Army Corps of Engineers approving any permits or easements for the Dakota Access pipeline," the senators said.

Experts say that the full environmental review requested by the senators could take several months.