"We know what is going on behind the scenes and there is a lot going on in the background that gives us confidence."
North West Leicestershire District Council gave Gillett's plans the green light in January but has now made it clear that unless certain crucial agreements are signed by 30 June then the planning permission regarding the planned £100m redevelopment will be revoked.
Before the development can get the go-ahead, Gillett needs the signature of circuit owner Tom Wheatcroft, and the leaseholder is optimistic that their dispute will be resolved in the coming weeks.
It emerged last month that Wheatcroft is seeking £2.47m in rent arrears from DVLL, who secured the 150-year lease in 2007, as well as forfeiture of the lease.
"We will be in a position to be able to sort that out very soon," said Gillett, who conceded the Donington development had been slowed by the global economic downturn.
Donington Park was the host of the 1993 European Grand Prix
"We are in in-depth meetings to button down the finances and you should see a resolution on this situation soon."
Donington Park secured a 10-year contract to host the British GP at the expense of current hosts Silverstone and is due to stage its first Formula 1 Grand Prix since 1993 in July next year.
Silverstone, which is owned by the British Racing Drivers' Club (BRDC), stalled over signing a new deal and F1 commercial rights holder Bernie Ecclestone was impressed by Gillett's plans to redevelop Donington.
However, Gillett's redevelopment has been delayed by a series of "trials and tribulations".
Firstly, the Motor Sports Association refused to grant the track a safety certificate which led to a cancellation of a number of events.
The debenture scheme to raise private investment was also due to launch at the end of March but has failed to get off the ground.
The legal dispute with the track owners, the council's concerns and the BRDC's insistence the race should return to Silverstone have added to Gillett's headaches.
I'm still working to the mantra that it's Donington or the Grand Prix goes outside of the UK
Donington leaseholder Simon Gillett
Despite the delays, Gillett is optimistic he can meet his self-imposed deadline of 1 April 2010 to revamp the track.
"We have a nine-month construction programme and that has never changed," said Gillett.
"We have always known we could construct everything we have to in nine months but we have the construction in hand.
"We need to be in a position to roll everything out by July 2009 but we are not panicking yet."
Gillett is determined to get Donington ready in time to ensure the British race, one of the sport's oldest Grands Prix, remains on the F1 calendar.
"I'm still working to the mantra that it's Donington or the Grand Prix goes outside of the UK," he said.
"We are here to try and save the British Grand Prix not to jeopardise it.
"At the moment the British Grand Prix doesn't have a home, we have stepped in and given it a lifeboat.
"Without the Donington circuit being available it would have gone already - we are here to make sure it stays here."
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