May 7 (Reuters) - U.S. energy firm Williams Cos said on Tuesday it still expects to overcome a pipeline dispute with rival Energy Transfer and complete its Louisiana Energy Gateway natural gas project in the second half of 2025.

The companies are in dispute over whether Williams proposed pipes can cross pipes owned by Energy Transfer.

Williams previously said the 1.8-billion cubic feet per day (bcfd) pipeline was originally set to come online this year, but the project was delayed to the second half of 2025 following the dispute with Energy Transfer.

"It's unfortunate that we're having these delays, but I'm very confident in our ability to finish this project ... We still expect the second half 2025 in service date," Williams Chief Operating Officer Micheal Dunn told analysts as part of an earnings presentation.

The project, which is under construction in Louisiana and Texas, will feed gas from the Haynesville shale field to the Gulf Coast where demand for the fuel is growing to supply several liquefied natural gas (LNG) export plants expected to enter service over the next few years.

Officials at Energy Transfer were not immediately available for comment.

Other energy firms, including Momentum Midstream and DT Midstream (DTM), have fought with Energy Transfer in court, accusing Energy Transfer of "blocking" their pipeline projects by not allowing them to cross Energy Transfer's pipelines in the area.

"I would say the tide is turning now on the (Energy Transfer) legal issues. We're seeing the appellate ruling from the Louisiana court that overturned the lower court ruling in the DTM case," Dunn said.

"We certainly think that's going to be the same outcome that we'll have on our cases ... ultimately, we're going to get our pipeline project built," Dunn said.

In other pipeline news, Williams' CEO Alan Armstrong told analysts the company planned to make an official U.S. Federal Energy Regulatory Commission (FERC) filing later this year for its proposed 1.6-bcfd Southeast Supply Enhancement gas pipeline project to supply markets in the Mid-Atlantic and Southeast.

"These markets are experiencing increasing gas demand from power generation and the reshoring of industrial loads," Armstrong said, noting utilities in the area have also announced "dramatic increases in their (power) generation needs based on data centers to be built in the region."

Armstrong said Williams would take advantage of supplies coming in from the 2.0-bcfd Mountain Valley gas pipeline from West Virginia to Virginia to meet some of that demand.

Equitrans Midstream said in April it expects its long-delayed $7.85 billion Mountain Valley project to enter service around May 31.

One billion cubic feet is enough gas to supply about 5 million U.S. homes for a day. (Reporting by Scott DiSavino; Editing by Michael Erman)