The government on Thursday locked horns with the northern region of Lombardy over its recent anti-smog law.
The government told the region surrounding Milan that pollution-fighting regulations approved in November were in breach of national laws and that it was turning to the Constitutional Court to get them overturned.
Under the November law, cars that are not fitted with catalytic converters will be banned from circulating in Lombardy as from October 1.
Buses, scooters and motorbikes without the converters will be banned from July.
Motorists who ignore the new rules face fines of 450 euros.
The law also introduces 'greener rules' for home and office heating systems.
But the centre-left government said on Thursday that the region was not allowed to impose traffic restrictions on main roads and highways and that any bans had to be flanked by alternative transport systems.
Lombardy regional government chief Roberto Formigoni blasted the government's decision.
"This is legally bizarre, scientifically wrong and politically a provocation... I would have expected support from the national government but once again, they have shown that their concern for the environment is limited to words and not action," the centre-right politician said.
"I'm sure the Constitutional Court will back us up given that the traffic curbs are aimed at reducing smog and protecting citizens' health," he added.
The Green party, which is a member of the governing coalition, also expressed disappointment, saying that the government should have worked together with Lombardy to find a solution to any problems posed by the regional law.
NORTHERN REGIONS JOIN FORCES IN ANTI-SMOG DRIVE.
Lombardy has included other northern regions in its anti-smog drive and on Wednesday signed an accord with them which includes a symbolic one-day traffic ban on February 25.
The initiative, organised independently of the central government in Rome, involves Lombardy, Piedmont, Veneto and Emilia Romagna and the provinces of Trento and Bolzano.
Announcing the plan on Monday, Formigoni said a pre-agreement had also been signed with Switzerland's Canton Ticino, just over the Italian border, to ally it with the traffic ban.
"The battle against pollution is widening, and this is important because the larger the area where action is taken, the quicker the results will come," Formigoni said.
The accord includes a complete ban on the most polluting vehicles by 2010.
Environment Minister and Green leader Alfonso Pecoraro Scanio welcomed the northern regions' plan of a one-day vehicle ban, saying it was an important way of raising public awareness.
"Now, the state and local authorities have to work together to implement structural, lasting measures," he added, referring to the need for greater use of railways and less polluting transport systems in cities.
One of the key pollution problems faced by big Italian cities, many of which are in the north, is fine particle, or PM10, pollution. Nitrogen dioxide and ozone levels are also said to be too high, although carbon monoxide and lead levels are under control.
In 2006 PM10 levels repeatedly exceeded limits that experts consider dangerous for health, according to environmental group Legambiente.
Under rules which came into effect in 2005 drastic anti-smog measures are called for if PM10 pollution rises above 50 micrograms per cubic metre for more than 35 days in a year.
In 2006 this limit was exceeded on at least 206 days in Palermo, 183 in Verona and 162 in Turin, the report said. Italy's two biggest cities, Rome and Milan, also fared poorly with 125 and 152 days respectively.
In recent years several cities have held occasional 'no-car' days in a bid to bring PM10 levels down. Others have introduced rules that limit circulation on Thursdays.
But critics protest that such one-off measures fail to tackle the real problem, which they say is structural and should be addressed with measures to permanently reduce the number of cars in circulation.
According to figures released recently by the World Health Organisation, between 2002 and 2004 PM10 caused an average of 8,220 deaths a year in Italy. It was responsible for 742 cases of lung cancer, 2,562 heart attacks and 329 strokes.
Legambiente's study said that if PM10 could be kept to an average of 40 micrograms per cubic metre, around 2,270 deaths could be avoided. If values fell to 20 micrograms, mortalities would be eliminated.
Pecoraro Scanio said last month that addressing the "emergency" depicted by recent pollution reports should be the government's top priority.
