Atlanta-based Norfolk Southern confirmed on Thursday that it is in merger talks with Union Pacific. The merger between two of the country’s major freight railroads would create a single U.S. railroad with service stretching coast-to-coast.

However, just two years ago, the STB approved the first major rail merger in more than two decades. In that deal, which was supported by big shippers, Canadian Pacific acquired Kansas City Southern for US$31-billion to create the CPKC railroad.

There is precedent in the potential merger after Canadian Pacific joined forces with Kansas City Southern in a $31 billion deal in 2023.