Fiat and General Motors on Monday declined to comment on a Financial Times (FT) report that said GM believes legal problems make invalid its promise to buy the Fiat Auto unit from next year, Reuters reported.

The news agency said GM may be forced to buy the remaining 80% of Fiat's loss-making car unit it does not already own from 2004, which many analysts had held on to as a last-ditch chance for the industrial group to pull free from its loss-making car business.

But GM in an SEC filing in March had said the "put" could become unenforceable "by reason of actions Fiat may have taken", Reuters added.
Reuters said that Fiat, in its own filing in June, said the sale of Fiat Auto was a "secondary possibility" after unveiling a €19.5 billion ($US22 billion) latest turnaround plan to revive the group.

According to Reuters, the Financial Times on Monday said Fiat CEO Giuseppe Morchio had told investors General Motors believed legal problems made its promise to buy the Fiat Auto unit from 2004 invalid, although he believed the put option was enforceable.

Separately, Reuters reported, Fiat chairman Umberto Agnelli said on Monday that discussions with its creditor banks on its three billion euro convertible loan would start again in September after the summer holiday.