(Reuters) – Democratic presidential candidate Hillary Clinton said in a Twitter post on Tuesday that drilling for oil and gas in the Arctic Ocean was “not worth the risk.”

“The Arctic is a unique treasure,” Clinton said.

The Obama administration on Monday gave Royal Dutch Shell final approval to resume drilling in the environmentally fragile ocean for the first time since 2012.

(Reporting by Emily Stephenson and Amanda Becker; Editing by Lisa Lambert)

Photo: U.S. Democratic presidential candidate Hillary Clinton speaks at the Iowa Democratic Wing Ding dinner in Clear Lake, Iowa, United States, August 14, 2015.  REUTERS/Jim Young