Blackstone Group reached an agreement to restructure the balance sheet of Hilton Worldwide as it looks to improve the flagging fortunes of its single largest investment.</br></br>Hilton's lenders and Blackstone are finalizing a deal that would cut its $20 billion debt load by about $4 billion, according to two people familiar with the negotiations. The agreement calls for Blackstone's funds to contribute $800 million of new equity, which will be used to buy back debt at a discount. It would also extend the maturity of some debt issues, these people said.</br></br>The restructuring will help shore up Hilton's finances as it struggles through a downturn in the hotel industry. For months, some analysts have said there was a risk that Hilton might not be able to generate enough cash to stay current on its $20 billion of debt. Without a restructuring, Blackstone could have been forced to sell Hilton assets to cover its roughly $900 million in interest payments, according to the analysts.</br></br>A Blackstone spokesman declined to comment.</br></br>A number of large leveraged buyouts -- walloped by the economy and large debt loads -- have managed to stave off default over the past year by restructuring their balance sheets. They've been helped by high-yield markets, which have proven eager to snap up new debt of even the weakest credits.