Atessa, July 9 - Fiat Group Chief Executive Sergio Marchionne on Tuesday declared that a 700-million-euro investment in the Sevel plant, near the Adriatic coast in central Italy, will be the automaker's last in its home country unless there are "clear rules" respecting company rights. "Without clear rules, the investment in Sevel will be the last," Marchionne told assembled plant workers in the auto factory located in the Val di Sangro, roughly 250 km due east of Rome near Italy's eastern coast. "We do not want to put announced investments up for discussion, but we cannot accept that violent behavior, and the boycotting of our efforts, become considered the exercising of 'rights' even on the part of authoritative institutions," Marchionne said. Earlier this month, the left-wing FIOM trade union won a battle with Fiat over worker representation at the carmaker in a landmark ruling at Italy's Constitutional Court. FIOM, the metalworkers' arm of Italy's biggest trade-union confederation CGIL, petitioned against being excluded from the company union representation bodies (RSAs) at Fiat's plants for not having signed the company's labour agreements. Fiat said it could do this on the basis of article 19 of the 1970 workers' statute. But the Constitutional Court said in a statement that it considered illegitimate the part of the article that said unions who did not sign the collective agreements applied at a company's plants could be excluded from RSAs, even if they had taken part in the negotiations. The Sevel plant directly employs 6,200 workers and supports about 4,000 jobs among suppliers. The factory has produced Fiat Ducato vans since 1981. Marchionne met with Abruzzo's regional governor, Gianni Chiodi, before the investment announcement at the plant. The governor and the archbishop of Chieti, Bruno Forte, were among the local leaders present at the announcement.