The US State Department said on Tuesday it supported Qatar's efforts to market Libyan oil on behalf of rebels trying to oust Muammar Gaddafi and that it believed - but was unsure - the reported sale was a one-time deal.

It was not immediately clear under what authority Qatar may have marketed the 1 million barrels of Libyan crude.

In addition to selling the oil, Qatar has delivered four shipments of petroleum products to the eastern port of Benghazi, the Qatari state news agency QNA said on Tuesday.

The oil sales and the delivery of the petroleum products potentially offer a lifeline to the Benghazi-based opposition, which is seeking - with the backing of Nato air power - to push out Gaddafi.

QNA said the international community endorsed the actions at the March 29 conference in London of the so-called Libya Contact Group about the crisis in the North African nation.

Asked if the group had authorized the sale, US State Department spokesman Mark Toner replied: "I can't speak for the contact group but we do certainly support those efforts.

"Obviously, it's important that the opposition does have the financial wherewithal that it needs to operate," Toner said. "... We support those efforts."

Asked if he knew of any Qatari plans for further sales of Libyan crude, the spokesman replied: "I am not ... I believe it was a one-off deal but I am not sure."-Reuters