General Motors is considering putting Opel up for sale again as management loses confidence its European arm will return to profitability, two German magazines reported.
Auto Bild and Spiegel Online said on Thursday that possible buyers could be Chinese carmakers or Germany's Volkswagen. The magazines cited no sources.
General Motors declined comment. Opel also declined to comment but its Chief Executive Karl-Friedrich Stracke called the reports pure speculation in a letter to employees.
Volkswagen had no comment.
VW, Europe's biggest carmaker which has almost 20 billion euros ($29.3 billion) available to spend, is already juggling deals with Porsche SE, MAN and Suzuki.
GM dropped plans to spin off Opel in 2009 after months of negotiations to sell it, and embarked on a drastic restructuring to get the unit, which lost $1.6 billion last year, back on track.
GM's Chief Executive Dan Akerson said in March that Opel was still losing money despite selling more cars.
Akerson is fed up with Opel, and the turnaround isn't gaining traction, said a person familiar with Akerson's thinking who declined to be named.
He is trying to think of all possibilities to improve performance. But a sale is wishful thinking.
GM has been recovering in the United States after a taxpayer-funded bailout and has been looking to its business in China, the world's biggest car market, to help drive growth.
European bankers said it would be difficult to sell Opel in the current environment.
Last time around, the German government and European countries that are home to Opel factories lined up a total of 4.5 billion euros ($6.57 billion) in loan guarantees to achieve a sale.
Now the German government is seen having its hands full with efforts to avert a sovereign default by Greece. Also, GM's relations with Berlin were soured after the U.S. carmaker performed a U-turn on talks to sell Opel two years ago.
A German government source said on Thursday Berlin was not involved in any talks over Opel at the moment.
Officials with the U.S. Treasury, which still owns 32 percent of GM's common shares, declined to comment.
Opel is expected to break even this year and show a profit in 2012. But its management has said it will likely take about five years to restore the brand's image in its home market after the carmaker appeared close to the brink for months.
CEO Stracke said in the letter to employees, which was seen by Reuters, that Opel was making very good progress.
Incoming orders are very good right now. For the factories in (Britain's) Ellesmere Port and (Poland's) Gliwice we have already added eight shifts to meet demand for the Astra, Stracke said in the letter.
The company also said in a statement it planned to shorten the traditional summer shut-down at its main German factory in Ruesselsheim to meet demand.
Opel's works council said the reports that GM was considering a sale of Opel were pure speculation and called on the parent company to deny them.
GM had so far kept Opel as it might otherwise lose technology and for other good reasons, Klaus Franz, head of the works council, said in a statement.
(Reporting by Jan Schwartz in Hamburg; Additional reporting by Rene Wagner in Berlin, Matthias Inverardi in Duesseldorf, Edward Taylor, Jonathan Gould and Arno Schuetze in Frankfurt and Ben Klayman in Detroit; Writing by Maria Sheahan and Peter Dinkloh. Editing by David Cowell)