The merger would create the United States’ first coast-to-coast rail network, spanning 50,000 miles and 43 states.

(Reuters) -Union Pacific said on Tuesday it would buy smaller rival Norfolk Southern in an $85 billion deal to create the first U.S. coast-to-coast freight rail operator and reshape the movement of goods from grains to autos across the country.

The largest rail union in the United States said Tuesday it intends to oppose Union Pacific's proposed $85-billion buy of smaller rival Norfolk Southern in regulatory proceedings, citing concerns about how the largest-ever buyout in the sector will affect U.