Hershey's candy bars are displayed at a gas station in Phoenix. Reuters

This story was updated at 11:35 a.m. EDT.

Hershey Co.’s share price jumped 21 percent Thursday morning, touching a record high of $117.79, amid news that Mondelez International Inc., the maker of Oreo cookies and Cadbury chocolates, has made a takeover bid for the company.

The Wall Street Journal first reported the tie-up, saying it would be a “blockbuster deal uniting two of the world’s best-known candy makers.” Hershey’s share price rally gave the company a market capitalization of about $25 billion.

Mondelez recently sent a letter to Hershey proposing the deal, according to the Journal. Terms of the deal were not known, the paper added.

Any deal would require the consent of the Hershey trust, which has about 80 percent of the company's voting rights.

Analysts have been skeptical of takeover bids for Hershey in the past.

"The Trust ... is outwardly very committed to keeping the company independent," Bernstein analyst Alexia Howard said in June last year. "So it's pretty much impossible for an activist to get involved or for the company to be bought."

Mondelez said it will protect jobs following a merger of the two companies, locate its global chocolate headquarters in Hershey, Pennsylvania (where Hershey's HQ has always been), and rename the company Hershey, according to the Journal’s report.

Hershey had a market value of $20.7 billion as of Wednesday's close, meaning a deal could value the candy maker at more than that. Mondelez had a $69 billion market value, the Journal said.

Reuters contributed to this report.