The deal will also include the acquisition of around 525 acres of undeveloped land adjacent to the plant, as well as Williams’ interest in the Ethylene Trading Hub in Mt. Belvieu of Texas.

Located in the US Gulf Coast region, the olefins facility produces around 1.95 billion pounds of ethylene per annum.

Williams Partners is planning to use the cash proceeds from the deal to clear its $850m term loan, in addition to funding a portion of its capital and investment expenditures.

Subject to customary closing conditions and regulatory approvals, the deal is expected to be completed in summer this year.

Once the deal concludes, the subsidiaries of Williams Partners will sign long-term supply and transportation agreements with Nova to offer feedstock to the Geismar olefins plant through its Bayou Ethane pipeline system in the US Gulf Coast.

Williams Partners’ general partner and CEO Alan Armstrong said: “When the Williams Olefins transaction closes, we expect to be at 97 percent fee-based revenues driven largely by natural gas volumes.

“Today’s announcements further strengthen our financial position to support Williams’ peer-leading, low-risk growth portfolio.”

Nova Chemicals president and CEO Todd Karran said: “This transaction provides us with the opportunity to acquire an operating facility with immediate, positive cash flow, and with access to new customers and the benefits of an experienced workforce.”