The United States Attorney General, Janet Reno, has ruled that no action will be taken against doctors who use a controversial law in the state of Oregon to help patients commit suicide.

She's overturned a decision by the Drug Enforcement Agency, which said that doctors who prescribe lethal doses of medicine to terminally-ill patients would face severe penalties.

The practice, known as doctor-assisted suicide, has won strong support from voters in Oregon, where it was sanctioned in law four years ago.