NEW YORK (CNN/Money) - Troubled energy firm Williams Cos. received a much-needed hand from Warren Buffett and the company's banks Thursday in the form of $3.4 billion in financing that will help stave off a bankruptcy filing this week.

Williams and other energy companies have come under pressure because of recent industry turmoil sparked by the collapse of Enron Corp. over an accounting scandal.

Williams has reached agreements with Buffett's Berkshire Hathaway Inc., Citigroup and Lehman Bros. for about $2 billion in secured debt and has sold $1.4 billion in assets, the company said, confirming earlier press reports.

"The company's top priorities have been to improve our financial position and resolve regulatory issues facing the company," CEO Steve Malcolm said in a statement.

The financing allows struggling Williams wiggle room to pay off some of its $15 billion in debt and to seek a partner for its energy-trading business, according to a Wall Street Journal report. The agreement also marks Buffett's latest big investment in the troubled energy sector since the recent collapse of Enron, according to the report.

Williams failed to renew unsecured bank loans last week that led to sharp downgrades of its credit rating, which in turn led to collateral calls and cash margins from trading partners.

Williams has repaid $300 million in debt that matured Wednesday but still has $500 million due by Friday, the New York Times reported.

Included in the $3.4 billion is an amended $700 million secured revolving credit facility and a new $400 million letter of credit. Williams said it also has a $900 million senior secured credit agreement with a group of investors led by Lehman Bros. and Berkshire Hathaway. It said that agreement is secured with the entire oil and gas interests of Barrett Resources, which the company acquired last year.

The company also sold several assets, including most of the subsidiary that owns the Mid-America Pipeline to Enterprise Products Partners L.P., raising $1.1 billion in net cash.

Williams also sold Jonah Field natural gas production properties in Wyoming to EnCana Oil & Gas for $350 million, as well as most of its natural gas production properties in the Anadarko Basin to Chesapeake Exploration L.P. for about $37.5 million. The EnCana and Chesapeake deals netted $308 million in cash.

Credit-rating agencies have expressed concern that Williams (WMB: up $1.23 to $4.18, Research, Estimates) won't be able to sell enough assets to lower its debt. Williams reported a second-quarter net loss earlier this week of $349.1 million, or 68 cents a share, largely because of losses from energy trading.

The arrangement marks Buffett's second big investment in Williams. In March, MidAmerican Energy Holdings Co., a unit of Berkshire, bought Williams's Kern River Gas Transmission Co. for $450 million. At the same time, it bought 1.47 million shares of convertible preferred stock for about $275 million.

Earlier this week, MidAmerican agreed to buy Dynegy Inc.'s Northern Natural Gas pipeline for $928 million and assume $950 million in debt.