Actress Daryl Hannah and Robert F. Kennedy, Jr. are among a group of activists gathering outside the White House in Washington, D.C. on Wednesday (13Feb13) to protest against the construction of a controversial oil pipeline.

The Splash star, a longtime environmental campaigner, has been a vocal opponent of the Keystone Xl project, a pipe designed to transfer crude oil from Canada to refineries on America's Gulf Coast.

The pair is joining with representatives from activist groups Sierra Club, and Committed Citizens to participate in the civil disobedience action in a bid to get U.S President Barack Obama to abandon the pipeline and move towards a cleaner energy source.

The actress took to her page to post a series of photographs of the protest, including a snap of herself with lawyer/activist Robert F. Kennedy, Jr. and his son Conor, who also joined the rally.

Hannah was arrested in Texas in October last year (12) and outside the White House in August 2011 after protesting against the pipeline.