The rails sector is on high alert following reports that Union Pacific (UNP) is focused on acquiring Norfolk Southern (NYSE:NSC), which could create the nation's first coast-to-coast rails network if the deal cleared regulatory and White House scrutiny.

Union Pacific , the largest U.S. freight railroad operator, is exploring a possible acquisition of Norfolk Southern to create a $200 billion coast-to-coast rail network, a person familiar with the matter said.

Union Pacific is in talks to merge with Norfolk Southern, according to The Wall Street Journal, in a deal that would shake up the railroad business in America.The Journal cited people familiar with the matter.