Slideshow ( 2 images )

(Reuters) - Morgan Stanley will receive a $375 million breakup fee if E*Trade Financial Corp walks away from its $13 billion deal for the discount brokerage, the U.S. bank said on Friday.

On Thursday, Morgan Stanley entered into a deal to buy E*Trade, the biggest acquisition by a major Wall Street bank since the 2007-2009 financial crisis.

E*Trade has been the subject of M&A speculation for some time, especially after Charles Schwab Corp said it would buy TD Ameritrade Holding Corp last year.

If Morgan Stanley terminates the deal due to antitrust issues, E*Trade would receive $525 million, Morgan Stanley said in a regulatory filing here.

The bank expects to complete the deal by the fourth quarter, and executives expressed confidence that it would meet regulatory approvals.