The opposing argument is that Mexican companies need monopolistic power to compete with overseas rivals, especially under the North American Free Trade Agreement.

Some worry that the new law will put them at a competitive disadvantage to their overseas rivals.

In proposing the change, the Administration's principal goal would be to buttress the ability of American companies to compete internationally against overseas rivals that often receive substantial Government support.

Corporate unhappiness with American taxation has grown as American companies increasingly compete with rivals abroad and argue that their overseas rivals pay lower taxes.

American company sales have increased 40 percent this decade, but the sales of overseas rivals in the United States market have nearly quadrupled.

A competitive world market made it essential for businesses to be at least as competitive as their overseas rivals.

Mr. Greenspan said he sympathized with bankers who want a freer hand to compete with other financial institutions and overseas rivals entering their turf.

This had weakened them internationally in comparison with their main overseas rivals.

Trying to fend off increasing competition from overseas rivals, led by Komatsu Ltd. of Japan, Caterpillar began a six-year modernization program in 1986.

The slide has cost shareholders more than $180 billion - losses comparable with those of overseas rivals like Vodafone and Deutsche Telekom.