Cleveland-cliffs Inc., the largest U.S. iron ore producer, said Monday it has agreed to buy the U.S. assets of ArcelorMittal, the world’s largest steelmaker, for about $1.4 billion in a cash-and-stock deal.

Upon completion of the acquisition, Cleveland-Cliffs will become the largest producer of flat-rolled steel in North America.

Arcelormittal’s shares have fallen 34 percent this year to 10.31 euros, giving it a market value of 11.4 billion euros ($13.3 billion) as of Friday.Cleveland-cliffs shares are down 30 percent so far this year and currently have a market value of $2.35 billion.