The measure would tighten controls already put in place in 2004 and give independent Switzerland one of the most rigid regimes governing the use of GMOs in Europe, including the 25-nation European Union that surrounds it.

Within the bloc, restrictions are specific to types of crops and temporary in nature, in contrast to Switzerland's proposal for a five-year blanket ban.

The moratorium specifically bans Swiss agricultural production using GMOs. The use of imported livestock feed containing GMO material would still be permitted and research on GMOs, including for the pharmaceutical branch, would be allowed to continue under the measure.

The debate pits those who say that GMOs offer more productive, disease-resistant crops and livestock against those who fear possible environmental fallout or unintended consequences of manipulating genetic codes.

GMO DIFFERENCES

Switzerland's legislative system allows for regular referendums giving voters a direct say in lawmaking.

Although not a part of the EU, Switzerland has not escaped Europe's deep-seated and often bitter divisions over GMOs.

The bloc started an effective moratorium on authorising new gene crops and products in 1998. This ended in May 2004, when the European Commission, the EU's executive arm, issued an approval for imports of a GMO maize type.

A move by a province of Austria to apply a similar moratorium by becoming a GMO-free zone was rebuffed by the EU's highest court, the European Court of Justice, in October. The court ruled that a regional GMO ban ran counter to EU law.

The EU has several laws to govern the import, use and cultivation of GMOs. If a particular GMO product is approved under one of those laws, that approval applies across the EU.

Swiss-based agro-technology firm Syngenta, the world's third-largest producer of GMO seeds, said the measure - if approved - would have little economic effect on the company but would send the wrong signals about Switzerland.

"This has no impact on us today because we do all of our research in the United States," said spokesman Guy Wolff. "But it is damaging for research in Switzerland and especially in gene technology."