WILMINGTON, Del. (Reuters) - A U.S. bankruptcy judge on Wednesday gave Elliott Management Corp 11 more days to formalize its plans to bid on Oncor Electric Delivery Co before the court approves the $9 billion offer for the utility from Berkshire Hathaway Inc.

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Judge Christopher Sontchi of the Delaware bankruptcy court pushed back the hearing for the approval of Berkshire’s merger agreement with Oncor, which carries a $270 million termination fee should it fall through, to Aug. 21 from Aug. 10.

Elliott, the largest creditor of Oncor’s bankrupt parent Energy Future Holdings Corp, said it needed more time to finalize the financing for its $9.3 billion offer, after securing about $1.4 billion in new equity for its bid so far. It had asked for a delay of 35 to 40 days.

If billionaire Warren Buffett’s Berkshire has not won court approval of its offer from the bankruptcy court by Aug. 21, it will walk away from the deal, Patrick Goodman, the chief financial officer of Berkshire Hathaway Energy, told Sontchi.

Berkshire’s all-cash bid already has regulators’ support and promises to pull Oncor, the largest utility in Texas, out of its more than three-year bankruptcy. Regulatory hurdles scuttled two earlier deals for Oncor.

Roger Wood, a Moelis & Co investment banker representing Elliott, told the court that 10 other investors had expressed interest in joining Elliott in its bid. If all of them put in the amount they had indicated, Elliott would raise between $9.7 billion and $11.85 billion, he said.

“We would be oversubscribed,” Wood said.

Some $3.7 billion of that investment interest came from a single investor in the form of proposed debt financing, Wood added.

Chad Husnick, an attorney for Energy Future, warned earlier that if the court does not approve Berkshire’s deal on Aug. 21, and Elliott subsequently fails in its attempt to acquire Oncor, Berkshire may return but at a lower price.

Elliott’s offer values Oncor at $18.5 billion including debt, above Berkshire’s current $18.1 billion valuation.

Even if Berkshire’s deal for Oncor closes, Energy Future may still face an uphill battle winning Sontchi’s approval for its Chapter 11 reorganization plan.

This is because Elliott, which owns more than two-thirds of a key piece of Energy Future’s unsecured debt, anticipates voting against the plan, people familiar with the matter said.

Sontchi could also be swayed by other creditors who favor a deal with Berkshire, which has said it can serve as a stable, long-term owner for Oncor.