Union Pacific , the largest U.S. railroad operator, could reach an agreement to acquire rival Norfolk Southern as soon as early next week, Bloomberg News reported on Friday, citing people familiar with the matter.

Union Pacific and Norfolk Southern are nearing a $200 billion merger that could reshape U.S. freight transport, raising hopes for efficiency and concerns over competition.

The combination of two large rail companies would create the first coast-to-coast network, but the deal could reduce competition.