WASHINGTON -

Vermont Sen. Bernie Sanders and four other Democratic senators are asking President Barack Obama to halt construction of the four-state Dakota Access pipeline until a full environmental review can be completed.
    
In a statement, the senators said Thursday the request is due to a federal appeals court denying the Standing Rock Sioux's motion for a temporary work stoppage in southern North Dakota within 20 miles of Lake Oahe. The feds stopped construction on land bordering and under the lake in order to review the permitting process.
    
An environmental review would likely delay the pipeline, which Dallas-based Energy Transfer Partners hopes to complete by the end of the year.
    
The White House didn't immediately respond to requests for comment.
    
The other senators are Patrick Leahy of Vermont, Dianne Feinstein of California, Ben Cardin of Maryland and Ed Markey of Massachusetts.