Signs reserve seats before a Senate Foreign Relations Committee hearing about the proposed Keystone XL pipeline project on Capitol Hill on March 13, 2014 in Washington

The United States announced Friday a fresh delay on a final decision regarding a controversial Canada to US oil pipeline, saying more time was needed to carry out a review.

A US State Department statement said eight federal agencies would be given "more time" for the submission of their views on the Keystone pipeline.

The pipeline, first tabled in 2008, is slated to cross US borders bringing oil from the of Alberta to refineries in the US state of Nebraska and then farther south to Texas.

It has been long delayed awaiting an environmental review from the State Department, and a final recommendation from Secretary of State John Kerry, a passionate advocate for the environment.

It has also been held up by a February ruling by a judge in Nebraska who said the proposed route of the 1,179-mile (1,900-kilometer) pipeline was unconstitutional.