SYDNEY (Reuters) -Australia's Origin Energy said on Thursday it had received a sweetened takeover bid from a Brookfield consortium, valuing the power producer at A$16.40 billion ($10.49 billion), days after its top shareholder rejected the previous offer.

The consortium led by Canada's Brookfield, which also includes EIC's MidOcean Energy, is now offering Origin shareholders A$9.53 per share, up 8.2% from the prior offer of A$8.81 apiece, and a 5.1% premium to its last closing price.

The increased offer is the consortium's "best and final" proposal, subject to no rival offer, Origin said in a statement.

Origin said it unanimously recommended shareholders vote in favour of the revised deal in the absence of a superior proposal.

Top shareholder AustralianSuper on Tuesday had rejected the prior offer, saying it was "substantially below" its estimate of long-term value for Australia's biggest energy retailer.

The deal requires 75% support from the votes cast at a shareholder meeting, scheduled for Nov. 23, meaning AustralianSuper's holding in Origin - the biggest at 13.68% - could be enough to scupper it if not all shareholders vote.

AustralianSuper and the Brookfield-led consortium did not immediately respond to requests for comment.

($1 = 1.5640 Australian dollars)

(Reporting by Sameer Manekar in Bengaluru and Scott Murdoch in Sydney; Editing by Chris Reese and Jamie Freed)