Esmark Inc. has offered to buy United States Steel Corp. for $35 a share, trumping an earlier bid from Cleveland-Cliffs Inc. US Steel shares spiked on the news, rising as much as 43%.

US Steel announced Sunday it had started a strategic review of alternatives after rejecting the offer from Cliffs, which was valued at about $32.53 based on Friday’s closing prices, to value the company at $7.25 billion.