MILAN, Italy (AP) _ Cie. Industriali Riunite SpA, a key holding company of Italian financier Carlo De Benedetti, announced Friday it will hold a joint news conference with American Telephone & Telegraph Co. here on Saturday.

Although the topic of the news conference was not disclosed, De Benedetti is widely expected to reveal the terms of a complex financial transaction under which AT&T will sell its 22 percent stake in the computer manufacturer Olivetti in exchange for a stake in CIR and some cash.

According to local press reports, AT&T's stake in Olivetti has been valued at 1.2 trillion lire, or $925 million.

A spokesman for the De Benedetti group couldn't immediately be reached.

AT&T Chairman Robert Allen is scheduled to address the news conference.

The transaction would end a six-year relationship between De Benedetti's Olivetti and the U.S. telecommunications giant. But AT&T's stake in CIR would guarantee the U.S. company's continued presence in the De Benedetti group.

In 1983, AT&T acquired a 25 percent stake in Olivetti and agreed to sell Olivetti personal computers in the United States under its own name. This relationship turned sour in recent years as AT&T's personal computer sales slumped in the United States.

Earlier this week, AT&T announced it had agreed with Intel Corp. to jointly develop personal computers that work in AT&T computer networks.

At the press conference, De Benedetti also is expected to announce plans to sell part of CIR's stake in Olivetti to a European partner. Among those rumored as potential buyers are Siemens AG of West Germany, Cie Machines Bull SA of France and STC PLC's International Computers Ltd. unit of Britain.

Olivetti's stock has risen sharply in recent weeks on rumors that a deal with AT&T was in the making.

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