CNH Industrial said its interim CEO, Derek Neilson, will continue on pending the selection of a permanent replacement for Marchionne.
"As a outcome, Mr Marchionne will be unable to return to work".
"Fiat Chrysler Automobiles N.V. communicates with profound sorrow that during the course of this week unexpected complications arose while Mr. Marchionne was recovering", the the official statement read.
Sergio Marchionne, who was replaced this week as CEO of the automaker, is in intensive care at a hospital in Switzerland, as reported by the Italian newspaper La Stampa and relayed by Crain's Automotive News.More news: Donald Trump says Putin responsible for Russian meddling in 2016 election
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Fiat Chrysler Automobiles on Saturday appointed Mike Manley to replace the seriously ill Sergio Marchionne as its CEO.Manley, 54, a native of England, has headed Jeep since 2009 and the Ram brand. He has been the head of the Jeep brand since 2009, and took control of the RAM marque in 2015. Ferrari, which appointed Philip Morris International veteran Louis Camilleri as its CEO, makes its quarterly presentation on August 1.
The company has named Mike Manley as its new CEO, who will assume the position as well as responsibility for areas within the North America Free Trade Agreement (NAFTA) immediately. Since taking over, he has overseen the growth of Jeep in the United States and is responsible for the brand's big push into the European market. Shortly afterward, the company announces a spinoff of luxury brand Ferrari.
Elkann didn't give details of Marchionne's health problems, adding that his "first thoughts go to Sergio and his family".
At the June appearance, Marchionne also predicted Fiat was about to eliminate its debt. He pledged to complete a turnaround plan initiated by his predecessor to end years of losses, and soon announced plans to revamp Fiat's organization to make it more efficient. CNH Industrial, the maker of Iveco trucks and Case and New Holland farm equipment, named as its chairman Suzanne Heywood, managing director of Exor, the holding company of Fiat's founding Agnelli family. The Italian-Canadian was responsible for reversing FCA's seemingly terminal slide into obscurity, returning the company to profitability in 2006. Both brands have formed the leading edge of Fiat Chrysler's North American strategy to move away from passenger vehicle production and focus on SUVs and trucks to meet market demand.