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

Union Pacific Corp. is nearing an agreement for a stock-and-cash deal for Norfolk Southern Corp. that would value the smaller rival at about $320 a share, people familiar with the matter said, in what would be the rail industry’s biggest-ever tie-up.

Union Pacific and Norfolk Southern could announce a tentative merger agreement as early as this week, according to a published report. Bloomberg cited sources familiar with the talks in its report on Friday.