OSLO (Reuters) - Eleven European Union nations breached ceilings for air pollution in 2012 despite plans to avert health-damaging smog of the sort that choked Paris this month, the European Environment Agency (EEA) said on Monday.

The number rose from 10 in 2011, with the addition of Malta to the list of states above national limits set for at least one of four pollutants from sources including industry and cars.

"Air pollution is still a very real problem," EEA executive director Hans Bruyninckx said in a statement of the national limits that had been meant to be achieved by 2010, pointing to high pollution across parts of western Europe this month.

"We need to improve this situation by making further emissions cuts," he said. Last week, Paris imposed a partial driving ban and made public transport free to combat high levels of smog.

Despite the violations, the Copenhagen-based EEA said that EU-wide emissions of each of the four pollutants - sulphur dioxide, nitrogen oxides, ammonia and non-methane volatile organic compounds - had declined from 2011-12.

Nine EU nations - Austria, Belgium, France, Germany, Ireland, Luxembourg, Malta, Slovenia and Spain - breached their nitrogen oxide limits in 2012, mainly because of persistently high emissions from cars and trucks, the EEA said.

Denmark and Finland exceeded the ammonia limits while Luxembourg was alone in overshooting the volatile organic compound ceiling. All countries met sulphur dioxide targets.

Violations of the limits can in theory end with fines, although none have been imposed.

(Reporting by Alister Doyle; Editing by Mark Heinrich)