France to propose new carbon tax - minister

* Constitutional Council annulled earlier attempt

* Economy Minister says some loopholes will be closed

* Government may tax businesses, but at cut rate-paper

By Sophie Hardach

PARIS, Dec 31 (Reuters) - France's government wants to salvage a carbon tax, scrapped on constitutional concerns, by closing loopholes for some businesses, Economy Minister Christine Lagarde said on Thursday.

The French Constitutional Council annulled the tax, hailed by President Nicolas Sarkozy as a ground-breaking tool to fight climate change, on Tuesday on the grounds that it offered too many exemptions.

After the Constitutional Council complained that some 93 percent of industrial emissions were exempt from the tax, Lagarde told French radio this would change in a reworked version to be presented next year.

"We are going to review the law for industrial sectors that are already part of the market for emission quotas," she said on RTL radio. Such businesses were previously given a free ride.

The law's many loopholes were needed to win over critics who feared business competitiveness, people in rural areas and workers whose livelihood depended on cars or boats would be unfairly punished.

Others accused the government of inventing new taxes to bolster depleted public finances.

France's politically influential farmers and fishermen in particular were granted tax relief under the law, and Lagarde promised they would keep that special status after the revision.

Business daily Les Echo reported on Thursday that the government wanted to bring businesses under the carbon tax regime without harming competitiveness, for example by applying a lower tax rate.

France's junior minister for ecology, Chantal Joanno, has announced the new version will be proposed to parliament in February and could come into force in April.

But Sarkozy might find it difficult to persuade lawmakers to revive the project so close to regional elections in March.

Sarkozy's defeat over the carbon tax follows the disappointing Copenhagen summit on climate change, dealing a double blow to his efforts to project himself as a "green" reformer. (Reporting by Sophie Hardach)