A small portion of the club's shares is listed on the New York Stock Exchange. The market capitalization was more than $4 billion as of Wednesday's close.

"We are willing and expect to go higher than that $3.9 billion," Zilliacus said in a statement.

United's current owners, the Glazer family, began looking at options including new investment or a potential sale in November, 17 years after they bought the record 20-time English champions for 790 million pounds ($971.70 million).

Zilliacus said he hoped the Glazer family would want "to go down in history as sellers who enabled the fans of Manchester United to become owners of the club".

As part of the bid, he expects to invite fans of the club from around the world to be co-owners and make sporting decisions for the team.

"I want the fans to feel that they have a say in all the key sporting decisions of the club," Zilliacus said.

Manchester United declined to comment.

Any sale of the club would likely exceed the biggest sports deal so far - the $5.2 billion including debt and investments paid for Chelsea - sources had told Reuters previously.

British billionaire Jim Ratcliffe, a life-long United fan and founder of chemicals producer INEOS, put in a bid for the club in February.

($1 = 0.8130 pounds)