Singapore's future place on the Formula 1 calendar remains up in the air, with circuit chiefs suggesting there is no guarantee a fresh deal will be sorted.
The race organisers and Bernie Ecclestone have been locked in negotiations for several months now trying to thrash out a fresh five-year deal - but there are disagreements about the size of the race fee.
Ecclestone has traditionally been eager for fees to increase, but amid a worldwide financial slowdown a number of events have requested that costs are reduced, and Singapore is no exception.
A claim by Ecclestone earlier this year that the matter had been resolved was strongly denied by Singapore organisers, who said that the terms being offered did not make the event commercially viable.
A statement said: "What is presently on offer from Formula One Administration is insufficient for us to commit to a full five-year extension."
Talks are expected to continue over this weekend's Singapore GP, and senior management figures are reluctant to expand on the situation until progress has been made.
However, a statement from the Singapore organisers suggested that a renewal was only 'possible' - which casts fresh doubts on the long-term future of the event.
"We are in the process of negotiating a possible renewal of the agreement and the outcome will be announced once discussions are complete," said the statement.
It is understood that although the original five-year deal for the race runs out after this year's event, there remain clauses in the contract that means the grand prix will likely take place until 2014 even if no contract beyond then is agreed.
Ecclestone is expected to make a statement about the race's future on Saturday.
Singapore was a part of the provisional 2013 calendar that was issued to teams this weekend, but was marked down as one of several events that was subject to confirmation.