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                                                                    EXHIBIT 99.4

                                [MCI LETTERHEAD]




INVESTOR CALLS: MIKE KRAFT
                    (202) 887-2028

MEDIA CALLS: MANUEL WERNICKY OR JANE LEVENE
                  (202) 887-3000

             MCI WINS BID FOR BRAZIL LONG DISTANCE OPERATOR EMBRATEL
                        IN WORLD'S LARGEST PRIVATIZATION

RIO DE JANEIRO - JULY 29, 1998 - MCI, through its wholly owned Brazilian
subsidiary Startel, today won the tender for 51.79 percent of the voting shares
of Embratel, the long distance company of Brazil. Of the Telebras companies
privatized by the Brazilian government today at the Rio de Janeiro Stock
Exchange, Embratel has the only nationwide and international network and is
directly connected to tens of thousands of business customers.

Embratel provides interstate long distance and international telecommunications
services, as well as over 40 other communications services, including leased
high-speed data, satellite, Internet, frame and packet-switched services.
Embratel is an ideal fit for MCI's and WorldCom's international growth strategy
and extends the companies' local-to-global approach. Embratel's wholly-owned
nationwide and international network meshes well with MCI's and WorldCom's
global initiatives and complements the companies' plans with Telefonica.

The offer of US$2.3 billion (R$2.65 billion) was within MCI's valuation of the
company. Forty percent of the bid price is payable within the next five days,
with the balance due in two annual installments.


                                     -MORE-


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Brazil is the world's fifth largest country, the ninth largest economy, nearly
twice the size of Mexico and almost five times the size of Argentina. Brazil is
Latin America's largest communications market representing almost half of the
entire communications market in Latin America. In 1997, Brazil's communications
market was valued at US$15 billion and had 16 million fixed telephone lines
growing at an annual rate of 17 percent.

MCI has over 50 years of presence in Brazil with offices in Rio de Janeiro and
Sao Paulo. In December 1996, MCI Systemhouse purchased a one-third interest in
Proceda, one of Brazil's leading international systems integration and
outsourcing companies. Today, MCI has offices in 21 countries in the region and
direct company investments in Mexico, Belize and Venezuela, in addition to
Brazil. MCI is the second largest carrier of international telephone traffic
from the U.S. to Latin America. The company's global network includes ownership
in the major cable routes from the U.S. to Latin America and 16 satellite earth
stations in the region. MCI is also the largest owner of the Pan American Cable
System now under construction--the largest ever fiber optic cable linking the
U.S. with Central and South America.

MCI, headquartered in Washington, D.C., is a leading provider of local-to-global
communication services to business, government and residential users. The
company's fast-growing portfolio of advanced data and IT services accounts for a
quarter of MCI's approximately $20 billion in annual revenue. MCI operates one
of the world's largest and most advanced digital networks, connecting local
markets in the U.S. to hundreds of locations worldwide. MCI has agreed to merge
with WorldCom, one of the world's fastest growing communications companies. The
merger will create MCI WorldCom, a company uniquely positioned in the U.S. local
and long distance markets as well as the global data and Internet markets.

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