LONDON (Reuters) - France's Total said on Wednesday it had informed Libya's authorities of plans to acquire Marathon Oil's stake in the Waha field for $4.5 billion (3.23 billion pounds) even though it believed it did not require their consent.

"The deal with Marathon has closed and Total owns Marathon's stakes in Libya. On the legal side, as far as we had informed the Libyan authorities ahead of the closing, our analysis is that there was no need to obtain an pre-authorisation," a Total spokesman told Reuters.

The French oil and gas giant is currently in talks with Libya's National Oil Corp (NOC) "in order to offer them the necessary reassurances on our intention to develop Waha," he added.

On Monday, NOC said it was "discussing arrangements" over Marathon's "planned sale of its shareholding in the Waha oil company concession" and that Marathon had not received NOC approval for the sale.

(Reporting by Ron Bousso; editing by David Evans)