Class I merger talk comes back to center stage as the Wall Street Journal reports Union Pacific is in early discussions with Norfolk Southern. We hosted a call with Littlejohn & Co.

Union Pacific is working with Morgan Stanley investment bankers to provide guidance on the potential acquisition of another Class I railroad, the online publication Semafor reported on Wednesday, citing people familiar with the matter.

CSX Corp. stock is up on reports that Union Pacific is interested in buying the Jacksonville-headquartered railroad company. CSX Corp.’s stock rose to its highest level of the year July 17 after a report that Union Pacific Corp. is seeking to buy one of the two major eastern railroads, CSX or Norfolk Southern Corp.

Shares of freight transportation company Union Pacific (NYSE:UNP) fell 3.2% in the pre-market session after reports revealed the company was considering a major acquisition of an East Coast railroad.

BNSF Railway and Union Pacific ( NYSE: UNP) have networks that connect the West Coast to the central and Midwest regions but do not, by themselves, offer uninterrupted coast-to-coast coverage. Meanwhile,

Berkshire might see a bid for CSX as a defensive maneuver if its chief rival, Union Pacific, seeks to create a transcontinental railroad.