President Obama has removed one of the last obstacles to oil drilling in the Arctic and granted Shell permission to develop new exploratory wells that could bring the company enormous profits.

The Guardian reports:

However, the drilling permit granted by the Interior Department on Wednesday bans Shell from drilling into oil-bearing zones until critical spill-response equipment is in place – and that equipment is aboard a damaged icebreaker en route to Oregon for repairs.

The restrictions could severely limit Shell's operations during the brief Arctic season, which winds down in late September. The company has spent $7bn and seven years trying to open up the Arctic to oil and gas drilling. …

… the potential short-term rewards for a company like Shell are enormous, with the Arctic ocean believed to contain about 20% of the world's untapped and recoverable oil and gas reserves.

So far, the company has got in one short – and disaster-prone – season of Arctic drilling, after its Kulluk rig ran aground on an island in late 2012.