Origin Energy Ltd. will ask investors to vote on a revised A$19.1 billion ($12.5 billion) offer from a Brookfield Asset Management Ltd.-led group next month, postponing a planned meeting after proxy results showed the existing proposal would fail.

The utility will hold a new ballot on Dec. 4 on the current A$9.43 takeover offer and has received an alternative plan under which Brookfield and partner EIG Global Energy Partners could acquire parts of the business at a lower price if that vote fails, Origin said Thursday in a statement.