Bank officials said the direct loan for the Australian natural gas project will help support an estimated 11,000 U.S. jobs and is the second-largest single-project financing in the institution's nearly 80-year history.

Leaders in the House of Representatives reached a deal on Friday to keep the bank operating past May 31, when its current charter expires.

The bill is headed to the House floor on Wednesday under an expedited procedure that requires a two-third vote for approval. Leaders rarely place a bill on the so-called suspension calendar unless they are confident it has enough support.

The legislation would raise the bank's lending cap over the next two-and-a-half years to $140 billion, from $100 billion currently, subject to certain conditions to address concerns about potential defaults.

The Senate must also approve the package and President Barack Obama sign it for it to become law.

Earlier efforts to renew the bank's charter ran into opposition from conservative Republicans, who questioned the need for the bank, and from Delta Air Lines, which wants the bank to stop making certain low-interest aircraft loans to foreign competitors like Air India.

The compromise package makes certain concessions for Delta, such as directing the Treasury Department to pursue negotiations aimed at eliminating subsidized government financing for large aircraft used on international routes.

Boeing is the Ex-Im Bank's biggest customer, but a variety of other manufacturers also rely on its service to make sales in markets considered too risky for private lenders.

On Tuesday, key House Democrats urged fellow lawmakers to support the bipartisan deal struck by House Republican Leader Eric Cantor and the chamber's No. 2 Democrat, Steny Hoyer.

"As Republicans wring their hands in a stale ideological debate over whether to support American exports, China and other countries are significantly increasing their assistance to help their domestic companies compete abroad," said Representative Sander Levin, the top Democrat on the Ways and Means Committee.

Ex-Im Bank President Fred Hochberg told reporters he was happy with the Hoyer-Cantor deal, even though it fell short of a four-year authorization sought by the Obama administration.

"It's a three-year authorization. It's $140 billion. It's a good number and it's going to create more jobs," he said.

Hochberg said he was hopeful the deal would pass because of the leadership role played by Hoyer and Cantor.

The Australian project, on Curtis Island in south-central Queensland, will produce natural gas from coal-seam wells and will have total capacity of nine million metric tons per year.

ConocoPhillips Co and Bechtel International are the principle U.S. exporters on the project, with numerous small businesses in Texas, Colorado, Nevada, California, Oregon and Oklahoma also providing equipment and services, Ex-Im said.

China Petroleum and Chemical Corp (Sinopec) and Kansai Electric Power Co Inc of Japan will purchase most of the LNG produced. China Ex-Im Bank and commercial lenders are also providing debt financing for the project, Ex-Im said.

(Reporting by Doug Palmer; Editing by Neil Stempleman and Leslie Adler)

By Doug Palmer