Sergio Marchionne, the chief executive of Fiat, has reiterated the Italian carmaker's "unwavering commitment" to its proposed alliance with Chrysler, the US carmaker.
But he is categorical that his company will not put in any cash at this stage.
Fiat is offering its latest technology, which would help Chrysler expand into the small car market, in return for a 20 per cent stake before an April 30 deadline set by the US government.
Marchionne told an analyst conference call on Thursday that Fiat would not put in cash for a minority stake and would only commit cash further down the road "at the relevant time as the need arises".
Washington has said that Chrysler, which is operating under US government emergency loans, will be sold off in pieces if the April 30 deadline is not met.
Marchionne, who has travelled several times to the US to work on the deal, said: "I see no reason why it cannot happen. I can only confirm our unwavering commitment to get this transaction done. We see benefits to both Fiat and to Chrysler.
"We need to work on helping Chrysler recover from this crisis. I think we do bring sufficient technology and know how to this organisation to justify acquiring an equity stake.
"This whole notion of attaching cash to the introduction of Fiat into Chrysler is something I find really unjustifiable."
'No direct contact'
Asked about reports Fiat is set to buy the European holdings of General Motors, another US carmaker, Marchionne said he had nothing to announce and that there had been no direct contact between the two carmakers as far as he knew.
"If an opportunity were to arise in a tangible way we would give it a really hard look, but I don't think we are there yet," he said.
On Thursday, Roland Koch, the governor of the German state of Hesse, had named Turin-based Fiat as one of the potential investors "lining up" to invest in GM's subsidiary, Opel.
Marchionne restates his position that a consolidation of the car industry would eventually leave only producers that can make five million to six million cars a year, and that can get one million cars out of any single platform.
He said that the Chrysler deal was one means to that end for Fiat.
Marchionne made the comments after announcing that Fiat had made a first quarter loss of $531m, its first poor figures since a turnaround engineered by Marchionne, who took over in 2004 and ended a 17-quarter run of losses.
The Marchionne turnaround of Fiat centred on shedding non-core businesses, trimming management and signing more than 30 strategic industrial alliances in order to share costs and enter new markets.
He also launched a series of successful new models, including Fiat 500, which he has said he would like to launch in the US under the Fiat brand, along with reintroducing the Alfa Romeo, which is something that would be done under the Chrysler alliance.
Fiat shares, which have nearly doubled since the Chrysler deal emerged in January, closed down 0.8 per cent at $9.68 in trading on the Milan stock exchange.