Moody's Investors Service on Thursday said it may cut its debt ratings on Burger King Holdings because of substantial debt that may be taken on to fund its acquisition by affiliates of 3G Capital.

Burger King, the No. 2 U.S. fast food chain, carries a corporate family rating of Ba2, the second-highest junk level, from Moody's.

In a statement, Moody's said its decision on the rating will consider how an acquisition would affect Burger King's debt protection measures, liquidity and overall risk profile.

"In addition, the review will consider the company's operating trends, which remain exposed to further deterioration in consumer spending and increased competition," Moody's said in a statement.

Burger King has agreed to sell itself to investment firm 3G Capital for about $3.26 billion in a deal analysts said would give the restaurant breathing room to fix its business.

The company is struggling with weak demand amid a sluggish economic recovery and persistently high unemployment.