Geneva ? The World Trade Organization said Friday that the European Union can impose $4 billion in sanctions against the United States a figure 20 times bigger than any sanction allowed in the past because of tax breaks given to U.S. corporations operating abroad.

Delighted by the verdict, the EU vowed to go ahead with plans to impose the sanctions by working on lists of targeted products, including everything from textiles to nuclear reactors, unless Washington ends the tax policy.

“The cost of noncompliance with WTO is crystal clear,” said EU Trade Commissioner Pascal Lamy. “The path is now clear for the EU to adopt sanctions if the United States does not repeal the … scheme expeditiously.”

Aside from the rhetoric, however, the amount was so huge and the stakes for U.S.-American trade relations so high that there seemed little chance of the EU actually implementing its threat.

Instead, experts said that the EU would likely use the figure as a yard stick in bargaining to force Washington to amend its law quickly.

Kimberly Pinter, director of corporate finance and tax for the Washington-based National Association of Manufacturers, said the EU may have been given too much to use.

“They’re like the little dog that caught the bus,” she said. “They’ve gotten something larger than they can use.”

As for any change to the U.S. law, a repeal would happen if an “adequate replacement” was on hand, she said.

The “foreign sales corporations” system lets companies with a foreign presence, such as Boeing Co. and Microsoft Corp., to exempt between 15 percent and 30 percent of their export income from U.S. taxes. By doing that, the price of their goods are lowered and more competitive than foreign rivals. Last year, the WTO ruled that it constituted an illegal subsidy.

The tax break, coupled with a second benefit not challenged by the EU, is expected to save U.S. companies an estimated $4.8 billion this year.

A WTO arbitrator ruled that the European Union was entitled to impose as much as $4 billion a year in trade sanctions to make up for European business lost because of the U.S. law. Washington had claimed the figure should be less than $1 billion.