'Both sides are unhappy': Obama's Arctic drilling green light heightens tensions

State Department official says administration's stance on oil drilling program continues to spur criticism as Hillary Clinton joins list of opponents

A senior official at the State Department has admitted there is an "obvious tension" between the US's commitment to combat climate change and its approval of Shell's oil drilling in the Arctic.

Shell was given the final green light by the Obama administration to drill off the coast of Alaska on Monday. Following the arrival of a key safety vessel, the Fennica, to the Chukchi sea, Shell was allowed to commence its drilling program.