June 28 (Reuters) - U.S. pipeline operator Williams

is in advanced talks to acquire rival natural gas pipeline

operator Momentum Midstream for about $5.5 billion, Bloomberg

News reported on Sunday, citing people familiar with the

matter.

The Tulsa, Oklahoma-based company is putting the finishing

touches on an agreement to buy Momentum from private equity firm

EnCap Flatrock Midstream, the report said, adding that a deal

could be announced in about a week.

Reuters could not immediately verify the report. Williams

Companies ( WMB ), Momentum Midstream and EnCap Flatrock Midstream did

not immediately respond to a request for comment.

The deal would give Williams additional capacity to move gas

from the Haynesville shale to U.S. Gulf Coast export terminals,

the Bloomberg report said.

No final decision has been made and EnCap could still opt to

retain the company, according to the report.

Williams is exploring acquiring U.S. natural gas production

assets as it looks to secure supplies for its offerings to

hyperscalers and data center clients, Reuters reported in

February.

Momentum Midstream operates around 4,000 miles (6,437 km) of

pipelines, serving more than 140 customers across its network,

according to the company website. It also serves 10 liquefied

natural gas facilities and 26 power plants.