The US federal government on Wednesday said it would open 3.9m acres of land in a designated petroleum reserve in Alaska for drilling as a means to help curb rising petrol prices.

“This is welcome news at a time when Americans are paying record prices at the pump,” said C. Stephen Allred, assistant US Secretary for Land and Minerals. “Together with proposed new production from other offshore and onshore areas, these increased supplies will help to stabilise energy costs.’’