SYDNEY–Sydney Airport said it agreed to a takeover proposal from a consortium of infrastructure investors that values the airport at 23.6 billion Australian dollars (US$17.4 billion), several months after the consortium first bid for the airport.

Shareholders still need to approve the deal, and the airport said it expects a shareholder vote to be held in the first quarter of next year. Various regulators will also need to sign off on the takeover.

The…