Hollywood actor Robert Redford has expressed his horror following a devastating oil spill in Arkansas last month (Mar13), insisting the incident made him feel "sick".

More than 20 homes were evacuated around the town of Mayflower after a pipeline ruptured and spewed thousands of gallons of oil over lawns, roadways and suburban streets on 29 March (13).

Redford has been a vocal opponent of plans to build a new pipeline, the Keystone Xl project, to transport oil from Canada to the U.S., and he is adamant the Arkansas incident should be seen as a warning.

In a blog for the Huffington Post, he writes, "When I see raw tar sands coursing through people's yards and across wetlands, it makes me sick. My thoughts are with the people in Arkansas who are dealing with this river of toxic mess. And my thoughts instantly move ahead to what could happen to farms, families, homes, and wild areas across our country if we support expansion of tar sands with permits for pipelines such as Keystone Xl.

"The answer seems clear, especially when we look at the graphic video footage from Arkansas: tar sands expansion rewards the oil industry while putting us all at risk of oil spills and climate change. That's a raw deal by any calculation."