GM and joint venture partner Dubai World have each agreed to make additional equity contributions of up to us$ 959 million, the company said in a filing with the Securities and Exchange Commission.
Las Vegas-based MGM said it had also agreed to partially guarantee the completion of CityCenter through a commitment to contribute up to another us$ 600 million to the joint venture.
The partners said last month they had finalized us$ 1.8 billion, and received another us$ 500 million in commitments, toward the us$ 3 billion in financing needed to complete the us$ 9.1 billion development of hotels, condominiums and retail outlets.
The project, which is slated to open late, next year, is under construction at the same time the US economy has stalled, weak consumer sentiment has tamed spending in Las Vegas and access to credit has dried up.
MGM agreed more than a year ago to sell half of CityCenter to government-owned Dubai World, which also plans to acquire a stake of up to 20 % in MGM itself.