In this file photo dated Monday, Jan. 9, 2017, Fiat Chrysler CEO Sergio Marchionne during a briefing at the North American International Auto show, in Detroit, USA. Marchionne said Thursday Jan. 26, 2017, in a conference call that discussions are "proceeding well" with U.S. environmental authorities over accusations that the company failed to disclose software that let vehicles emit more pollution than allowed. (AP Photo/Carlos Osorio, File)

Fiat Chrysler's CEO says discussions are "proceeding well" with U.S. environmental authorities to get 2017 diesel models certified so they can be sold.

Sergio Marchionne said Thursday in a conference call that the company was "in the midst of some pretty intense discussions" with both the Environmental Protection Agency and the powerful California Air Resources Board.

He said he hoped discussions over 2017 models could be concluded "relatively quickly."

The EPA toughened testing for diesels from all automakers after Volkswagen was caught equipping cars with software that let them cheat on emissions tests. That has kept a number of models off the market for now.

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