Washington

ROYAL Dutch Shell and any oil drilling company that prospects in the Arctic Ocean must boost safety practices to prevent spills in the frigid and often hostile waters or mitigate the impact, US regulators proposed.

The Interior Department's first Arctic-specific drilling rules respond to mishaps that plagued Shell's efforts three years ago, by shortening the drilling season and requiring companies to have a backup rig nearby. Shell had already agreed to do much of what's in the proposal as part of its 2012 exploration plan, which was suspended after the stumbles.