(Reuters) -BNSF Railway has hired Goldman Sachs and CSX Corp is in talks to bring on financial advisers, as rival Union Pacific's interest in acquiring Norfolk Southern sparked a wave of deal preparations that could reshape the U.S. freight rail industry, sources said.

The moves by BNSF, owned by Warren Buffett's Berkshire Hathaway, and Jacksonville-based CSX come after Union Pacific began exploring a potential acquisition of Norfolk Southern, which could create a $200 billion coast-to-coast rail network and mark the most significant consolidation in the sector in decades.

Any potential deal is expected to undergo intense regulatory scrutiny and remains far from certain.

Goldman and CSX declined to comment. BNSF did not immediately respond to a Reuters request for comment. 

Shares of Norfolk Southern were up 2.4% in extended trading.

Berkshire bought BNSF in 2010, paying $26.5 billion for the 77.4% of the railroad it didn't already own.

The last major rail merger occurred in 2023, when Canadian Pacific acquired Kansas City Southern, forming the first network to span Canada, the U.S. and Mexico. That deal followed a failed bid by Canadian National, underscoring how competitive pressures can quickly escalate in the sector.

In 2024, Union Pacific led the industry with $24.3 billion in revenue, followed by BNSF, CSX, Canadian National Norfolk and Canadian Pacific Kansas City.

Talks between Union Pacific and Norfolk Southern are still in early stages, the people said. Any merger would require approval from the Surface Transportation Board, which could take up to two years.

CSX would be a better fit for Union Pacific than Norfolk Southern, said David O'Hara, managing director at MKP Advisors.

"With first-mover advantage, Union Pacific will buy whoever in the East wants to make themselves available," O'Hara said. "And whoever is left out in the cold ultimately will get bought by Burlington Northern - that will almost have to happen."

(Reporting by Sabrina Valle in New York, additional reporting by Jonathan Stemple in New York, Anshuman Tripathy and Arsheeya Bajwa in Bengaluru; Editing by Anil D'Silva and Lincoln Feast.)