A merger between Fiat Chrysler and Peugeot maker PSA to create the world's fourth largest carmaker is the best way for the two companies to weather the coronavirus crisis, the Italian-American group's chairman said on Friday.

Echoing similar comments from PSA Chief Executive Carlos Tavares on Thursday, FCA Chairman John Elkann told shareholders the COVID-19 crisis had not delayed plans to finalise the tie-up by the first quarter of next year.

"The COVID-19 crisis has further underlined the compelling logic of this merger," he said.

"The excellent rapport that has been established in these months, also at a personal level, with (PSA Chairman) Louis Gallois, Carlos Tavares and their teams is strong evidence of our shared vision, determination and purpose."

Tavares, who is due to become the merged group's CEO, said on Thursday he was confident that the merger would proceed as planned and deliver synergies of at least 3.7 billion euros ($4.2 billion).

FCA Chief Executive Mike Manley said on Friday the group was fully aware that the pandemic would be here "for the foreseeable future", but that the carmaker could rely on its portfolio of brands and a solid business plan to cushion its impact.

"These are the great strengths that FCA brings to the merger with PSA," he said

"I firmly believe that as the market recovers, as it will, we will return to the positive momentum we were experiencing prior to this horrible pandemic".

Manley also said a European Union antitrust probe into the merger was not expected to delay the timetable to completion.

"Both companies will continue to engage with the European Commission in the same constructive spirit that has defined our proposal from the outset," he said.

EU antitrust regulators earlier this month said the proposed tie-up might harm competition in small vans in several European countries, as they opened a four-month investigation into the deal.

(Reporting by Giulio Piovaccari; Additional reporting by Gavin Jones; Editing by Francesca Piscioneri and Jan Harvey)