It is estimated that U.S. farmers lose about $300 million a year in sales to the EU because of the biotech moratorium. Lifting the ban could open the way for shipments of American corn, for example, since about one-third of the U.S. crop is genetically modified to help fend off pests.

The European Commission has been working to lift the moratorium on product approvals and it could do so sometime this spring or early summer.

But it still would take a while for actual product approvals. Also, the United States has expressed concern that if the moratorium is lifted, burdensome biotech product labels and traceability standards would then be employed to block trade.

While the EU is eager to cash in on biotech commerce, it must balance that desire against deep consumer mistrust of what are commonly known as "Frankenfoods."

Top Bush aides could meet early next week to decide on whether a WTO complaint will be filed. The EU has warned that doing so would merely inflame strong consumer resistance to biotech goods.

Hastert's letter to Bush, which was signed by nine other House Republicans, repeated the oft-heard contention that the United States has to stand up to the EU so that other countries do not impose similar barriers to biotech goods.

On Monday, Senate Finance Committee Chairman Charles Grassley, a Republican from the major farm-state of Iowa, said the Bush administration should "get off its duff and make a decision" to file a WTO complaint against the EU.