Harrah's Entertainment Inc. has tentatively cleared the last remaining regulatory hurdle to the largest casino buyout ever.Harrah's said Monday that the National Indian Gaming Commission has approved the company's $17.7 billion purchase by private equity buyers Apollo Management and Texas Pacific Group, pending final commission review. That conditional approval means Harrah's can go forward with the deal, which is expected to close in early 2008. No further regulatory approval is required.

Officials with Harrah's in Las Vegas and the Indian gambling commission in Washington did not immediately respond Monday to messages seeking further comment.

Harrah's and the buyers received the go-ahead for the deal last week from the Nevada Gaming Commission, capping a 10-week campaign to obtain approvals from state gambling regulators in New Jersey, Pennsylvania, Louisiana, Iowa, Missouri, Illinois, Indiana and Mississippi.

Harrah's, which had nearly $10 billion in revenue last year, operates more than 50 casinos including Caesars and the Imperial Palace in Las Vegas and Bally's in Atlantic City. Indian Gaming Commission approval is needed because Harrah's operates several tribal casinos as well.

The company's stock was up 51 cents to $88.84 in Monday trading. The buyout deal calls for Apollo and Texas Pacific to pay $90 per share.