The American businessman was named as preferred bidder to take the club out of administration on 6 April.

BBC Radio Derby report that Kirchner has failed to close the deal, despite having his period as preferred bidder extended twice.

It is also understood that funds promised by the 34-year-old to pay Derby wages for May have not arrived.

The English Football League conditionally approved the takeover when contracts for the sale of the club had been exchanged on 17 May.

At the time, the EFL said "the terms of a Membership Agreement" had been agreed with the American's 9CK Sports Holdings Limited company to allow the sale of the club.

Derby's administrators Quantuma had said the takeover was conditional on the sale of Derby's Pride Park home ground, which is still owned by former majority shareholder Mel Morris.

Meetings between Kircher, his representatives, Morris and Derby City Council, who have said they were exploring options to buy the ground, have failed to resolve the issue.

If the deal does fall through, it will be the second time an attempt by Kirchner to buy the club has failed.

An initial bid was withdrawn on December before the American revived his interest in April after an attempt to buy Derby's then-Championship rivals Preston North End collapsed just days earlier.