(Reuters) - Time Inc <TIME.N>, the publisher of Time, People and Fortune magazines, has rejected a takeover bid from billionaire investor Edgar Bronfman Jr., the New York Post reported on Monday.

Bronfman offered $18 per share, the Post reported, representing a premium of 30.4 percent to Time Inc's Friday close and valuing the publisher at $1.78 billion.

Time Inc's shares jumped 18 percent to $16.05 on Monday.

Bronfman, who is a managing partner of private equity firm Accretive LLC, made the bid along with Russian-born billionaire Leonard Blavatnik, the founder of holding company Access Industries, and Israeli businessman Ynon Kreiz, the Post reported.

Bronfman, a former chief executive of Warner Music Group, has a long history in the media and entertainment world. His family made its fortune from Seagram's, once the largest distiller of alcoholic beverages in the world.

A spokeswoman for Time Inc declined to comment. Access Industries did not immediately respond to a request for comment, while Bronfman could not immediately be reached.

Time, like many publishers, has been hit by a decline in print ad sales as advertisers spend more on other media and readers increasingly move online.

Digital advertising has been the lone bright spot for the company, with revenue rising 63 percent in the latest quarter.

Up to Friday's close, Time's shares had fallen 12 percent this year and about 42 percent in the last two years.

(Reporting by Aishwarya Venugopal in Bengaluru; Editing by Sai Sachin Ravikumar)