After meeting with Brazilian officials in Sap Paulo recently, former F1 supremo isn't confident in the future of the Brazilian Grand Prix at Interlagos.
The 86-year-old was entrusted by F1's new CEO Chase Carey to convince Brazilian officials to secure the future of the race.
But Ecclestone, who returned to the paddock in Bahrain two weeks ago, isn't sure the venue will remain on the calendar beyond 2020.
"Chase (Carey) asked that when I went to Brazil, 'Would I speak to the president about the race', which I had done before," Ecclestone told Brazil's UOL Esporte.
"But it seemed pretty obvious to me that he had several other things to worry about than Formula 1.
"So we went to the mayor of Sao Paulo, but he does not want to spend a single dollar -- he wants to sell the circuit," explained the former F1 supremo.
Ecclestone himself was subsequently linked to a potential bid for the embattled Interlagos facility.
"He (the mayor) asked me if I would be interested. We can get him to agree that when the sale happens, whoever buys it will have to keep the Formula 1 circuit.
"Then it's a case of finding an organiser for the race, which is a bit more difficult," he explained.
"So I think that if we can't do anything, we will lose it, for sure."
However, UOL reports that Interlagos race promoter Tamas Rohonyi was in Paris this week for contract talks with the FIA.
"The race will be there 100 per cent until 2020," Ecclestone added.
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