Bernie Ecclestone says the Brazilian GP will remain at Interlagos as long as planned upgrades to the circuit go ahead.
Ecclestone, in Sakhir on Friday for the Bahrain GP, also said F1 was "talking to quite a few countries" about being added to the calendar. Among them were Thailand, Mexico and Turkey.
He said Sao Paulo Mayor Fernando Haddad wrote to guarantee the upgrades at Interlagos.
"We have been waiting long enough," Ecclestone said. "If Sao Paulo does what they say they are going to do, we don't need to move. They know what the deadline is. If they don't do it pretty soon, it will be gone."
Ecclestone said it was worth examining Bahrain's request to return to the season-opening slot, which was handed to Australia when the Bahrain race was cancelled in 2011.
On Thursday, Zayed Alzayani, the chairman of the Bahrain International Circuit, said he would prefer the opening slot because it would allow the teams to remain here longer and would open the door for hosting pre-season testing on the circuit.
Ecclestone also reaffirmed his opposition to the turbocharged 1.6-liter V6 engines from 2014, which will replace the 2.4-liter V8s. He said he feared the switch would prompt a "fuel economy run."
Proponents have trumped the fact the new engines will be much more efficient but detractors fear the extra cost will further widen the gap between big and small teams.
"The FIA would be happy to have a look. It's the manufacturers that don't want them touched," Ecclestone said. "They always have said they made a big commitment to get where we are. I've explained if one of you have got it wrong, which will happen, whatever commitment you have made, you will have to spend an awful lot more to get it right. What we have got at the moment is good. There is nothing wrong with it."
As for the Pirelli tires, Ecclestone dismissed concerns from several teams including Red Bull that they are degrading too fast and resulting in races that are more like chess matches than a spectacle.
"Pirelli have done an absolutely first-class job," he said. "They have done what we asked them to do, make sure we didn't have tires that didn't last even half the race. ... If by chance they (Red Bull) get the tires to work here, they will probably be the best tires. Up until now, they haven't got it to work so it's not good."