Williams, a US-based natural gas company, is reportedly close to acquiring Momentum Midstream in a transaction valued at approximately $5.5bn.

The deal is said to be in the advanced stages and could be made public in around a week's time, reported Bloomberg. If executed, it would be one of the largest deals in Williams’ history.

The proposed acquisition would involve Williams purchasing Momentum Midstream from EnCap Flatrock Midstream.

EnCap is a private equity firm established in 2008 by Flatrock Energy Advisors and EnCap Investments.

However, the sources indicated that no final decision on the deal has been reached and EnCap could ultimately decide to retain the asset.

Williams, based in Tulsa, Oklahoma, currently manages more than 30,000 miles of natural gas pipeline infrastructure.

By acquiring Momentum Midstream, the company would expand its capacity to transport gas drawn from the Haynesville fields in East Texas and northern Louisiana to export terminals along the US Gulf Coast.

Momentum Midstream operates approximately 4,000 miles of pipelines serving ten liquefied natural gas (LNG) facilities and 26 power plants.

The company has focused its growth strategy on acquiring assets in East Texas and Louisiana.

Last year, Momentum Midstream commissioned the 250-mile NG3 pipeline system with a total capacity of 2.3 billion cubic feet per day. NG3 carries gas from the expanding Haynesville basin to LNG facilities centered around Gillis, Louisiana.

On 26 June, Williams’ shares closed 0.5% higher at $77.92 on the New York Stock Exchange, resulting in a market capitalisation of $95bn.

In April this year, Williams started building the Northeast Supply Enhancement (NESE) project, which will expand its Transco pipeline network.

The development is expected to boost the Transco system’s daily capacity by 400,000 dekatherms, enough to supply energy to around 2.3 million households in Pennsylvania, New Jersey and New York.