* Environment minister issues ultimatum to industry
* Tobacco firms must make proposals by September
* Otherwise they face new regulations
By Geert De Clercq
PARIS, June 14 (Reuters) - France will force tobacco companies to help end the scourge of cigarette butts that litter streets and contaminate water, unless they take voluntary action in the next three months, a government minister said on Thursday.
The city of Paris picks up 350 tonnes of cigarette butts every year despite wall-mounted ashtrays and the threat of a 68 euro ($80) fine for anyone caught throwing one on the street.
"If no effective commitments are proposed by September, the government will force the industry to get involved in the collection and elimination of its waste," junior environment minister Brune Poirson said ahead of a meeting with industry representatives.
The ministry estimates 30 billion butts are thrown away in France every year, of which more than four in 10 end up on beaches, in forests, rivers and the sea.
A single filter can contaminate hundreds of litres of water because of the chemical substances it contains, and can take more than a decade to decompose, Poirson said.
The government has not said what measures it might impose, but one official said a mandatory recycling scheme was an option.
"The ministry will not be brutal on the method, but will be firm on the objectives. Pollution is major, so the commitments cannot be minor," the official said.
British American Tobacco, whose brands include Lucky Strike and Rothmans, said in a statement it would work with the government to educate smokers, and distribute pocket ashtrays. But it rejected new taxes.
"It is not up to companies, smokers or citizens to pay, via additional taxes, for the cost linked to the clean-up of cigarette butts," BAT public affairs director Eric Sensi-Minautier said.
Imperial Brands, which sells the French Gauloises and Gitanes brands, said it encouraged smokers to dispose of butts responsibly. It said it had no plans to alter its filters to make them less polluting.
Other leading brands in France are Philip Morris' Marlboro and Japan Tobacco's Camel.
Cigarette butts are the world's most common form of litter, with an estimated 4.5 trillion thrown away every year, according to medical journal Tobacco Control.
(Reporting by Geert De Clercq; Editing by Luke Baker and Robin Pomeroy)
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