British publisher Robert Maxwell said Friday he will launch a $2.1 billion cash tender offer for Macmillan Inc. next week, but made clear his main interest is acquiring its information services business. Macmillan already is the subject of a $1.9 billion bid from Robert M. Bass Group Inc., a Texas-based investment group. In a letter to Macmillan, Maxwell said he would drop his $80-a-share tender offer if Macmillan would sell him the information company, which Macmillan proposed to separate from its publishing business in a corporate restructuring. Maxwell said his Maxwell Communications Corp. PLC would be willing to pay ``not less than $1.1 billion'' in cash for the information business, noting that Macmillan's investment bankers had valued it at ``a range of $800 million to slightly in excess of $1 billion.'' In the letter, Maxwell also told Macmillan Chairman Edward P. Evans he was ``willing to explore other forms of transactions with you'' that would allow current shareholders to continue to hold a significant stake in the company. Maxwell also reitereated he wanted to retain Macmillan management. Macmillan declined to comment on Maxwell's proposals. On Wall Street, the price of Macmillan stock rose $1.50 a share to $83.25, indicating investors expected the bidding to escalate. ``Some people suggested Maxwell isn't serious, but by launching a tender offer at $80 a share on Monday, we see he is serious,'' said Bert Boksen, who follows the publishing business for the brokerage Raymond James & Associates in St. Petersburg, Fla. But Boksen said by making the alternate suggestion that he be sold the information assets, Maxwell ``identified the piece he is most interested in.'' ``I think Macmillan is backed up against the wall and will try to find a white knight,'' he said. He said Macmillan could be worth $90 a share. The overture from Maxwell came only three days before a scheduled court hearing in Delaware on whether Macmillan should be allowed to proceed with its proposed restructuring. The restructuring, announced in late May, would split the company into separate publishing and information services concerns and pay shareholders a special dividend of $52.35 a share in cash. That plan was advanced after the Bass Group proposed to pay $64 a share for the Macmillan stock it did not already own. The Bass Group subsequently sweetened its offer twice, and launched its own tender offer for Macmillan at $75 a share. The Bass Group won an order from Delaware Chancery Court blocking Macmillan from proceeding with its restructuring. Macmillan appealed the decision to Delaware Supreme Court, which scheduled a hearing for Monday. Maxwell disclosed his interest in Macmillan in mid-July, saying he would be interested in paying $80 a share for its 25.9 million shares in a friendly transaction. A Maxwell spokesman said Friday that the tender offer at that price would commence on Monday. It is contingent on dropping the restructuring plan, among other things, but Maxwell said it is not conditioned upon obtaining necessary financing. Late last month, the Macmillan board rejected the $75 a share offer from Bass as inadequate, but took no position on the Maxwell proposal. Macmillan spokesman David Jackson refused Friday to comment on whether the board has since met to discuss the Maxwell proposal, or anything else. Maxwell has vowed to make Maxwell Communications one of the world's biggest media and communications businesses. Through that company and Pergamon Press, Maxwell controls the Mirror Group of newspapers in Great Britain, is one of America's largest printers of magazines and catlogues and has extensive holdings in publishing academic and scientific journals.