The US tycoon's organisation made the claim yesterday, despite financial difficulties at one of his US subsidiaries.
George Sorial, the Trump Organisation executive in charge of the golf resort development near Balmedie, told The Scotsman that Mr Trump had recently "increased his cash position" and has the money on hand to fund the development.
The Scottish Government gave the go-ahead to the project earlier this month, after strong opposition from locals drove the development to a public inquiry.
Mr Trump's plan for the site includes two golf courses and a 450-bedroom hotel and housing, as well as holiday apartments and golf villas.
Mr Sorial said: "The money is there, ready to be wired at any time. I am not discussing where it is, whether it is in a Scottish bank or what, but it is earmarked for this project. If we needed to put the development up tomorrow, we have the cash to do that. It is sitting there in the bank and is ready to go."
He added: "I don't think anyone in Scotland has anything to worry about."
Mr Sorial's comments came as it emerged that Mr Trump is embroiled in a court case over the funding of his Trump International Hotel and Tower in Chicago.
Mr Trump, who is due to visit Scotland in two weeks to meet his Scottish development team, has recently filed a suit against a group of lenders – led by Deutsche Bank – on the 92-storey project, in an attempt to extend his $640 million (430 million) construction loan.
The case has raised questions in the US as to whether the high-profile real-estate tycoon has been hard-hit by the property downturn.
Paul Johnston, one of the three Aberdeenshire councillors who stood up at the public inquiry to oppose Mr Trump's plans, said local people were worried the economic downturn could leave the project started but unfinished.
He said: "The worry that the project may be left unfinished was a specific point that was raised by community councils at the public inquiry. Everybody is now watching how Donald Trump is faring internationally with a little bit of interest.
"Even if he does have the money to build the project, then he also has to sell the development once it is completed, which is another worry."
But Mr Sorial insisted that Mr Trump was cashing in on the economic downturn, pointing to his recent acquisition of a golf course in New Jersey and adding that another similar buy-out was on the cards.
He said: "There is an economic downturn globally, but we have managed to use that to our advantage. We have bought up some projects that are discounted by 30 to 40 per cent.
"Having cash in a downturn like this is a good position to be in. We have a very diverse business. We are talking about an organisation that has its own TV show, numerous lines of products including clothing, vodka and so on. It is not about one little project."
He added: "As we have said all along, Aberdeen is a project we have chosen to fund with cash. Mr Trump has recently increased his cash position and we have no need for a bank loan in respect of the Aberdeenshire project."