ATESSA, Italy (Reuters) - Fiat (>> Fiat SpA) Chief Executive Sergio Marchionne said on Tuesday the automaker would put investments in new models on hold until there is clarity over the impact of a court ruling that cast doubt on the company's labour relations.

Italy's constitutional court ruled last week that a clause in the country's labour law from the 1970s that allows Fiat to bar the Fiom metalworkers' union from representing workers on its factory floor was unconstitutional.

"Before taking any further initiatives in Italy, we need a clear legal and normative framework," he said.

Marchionne, speaking to workers at the carmaker's Sevelsud plant in central Italy, said he was open to meeting with Fiom leader Maurizio Landini to discuss what measures could be taken, based on a common understanding that Fiat's 2011 labour contract would not be revised.

Fiat has invested in several of its Italian factories in exchange for concessions from its labour unions for giving more flexible work conditions.

Fiat's investments are crucial to Italy's economy, which has been in recession for two years and has record unemployment.

Fiat has also promised billions of euros in new investments to build Jeeps and Alfa Romeos for export to the United States and elsewhere in Italy.

Fiat and its sister company Fiat Industrial (>> Fiat Industrial SpA) have invested 23.5 billion euros ($30.23 billion) in Italy from 2004 to 2012, he said.

($1 = 0.7773 euros)

(Reporting by Alberto Sisto, writing by Jennifer Clark. Editing by Jane Merriman)

Stocks treated in this article : Fiat SpA, Fiat Industrial SpA