UPDATE: London Irish must pay all staff their full May wages on Wednesday or face being withdrawn from the English Premiership.
The Rugby Football Union (RFU) said it is giving owner Mick Crossan the chance to meet payroll as scheduled on Wednesday.
The offer of a deadline extension to complete a takeover will be withdrawn if the wages are not paid.
An American consortium is in discussions to take control of London Irish, but has yet to provide proof of funds to the RFU, as well as other documentation needed for the purchase to be approved.
The Exiles have reported debts of £30 million ($37 million) and are fighting to avoid becoming the third top-flight club to be suspended over financial issues this season after Wasps and Worcester.
“The RFU club financial viability group met yesterday evening. It noted the conditions set by the RFU had not been met and considered the application for an extension to the deadline,” an RFU statement said.
“It was agreed to defer the decision for 24 hours to establish if the club is able to honour the commitment it has made to staff that they will be paid for the month of May. The group will meet again this [Wednesday] evening.”
London Irish do not own their own ground, with the Exiles now playing their home games at Brentford football club’s Community Stadium, making it more difficult to generate revenue.
Coached by former Ireland boss Declan Kidney, London Irish narrowly missed out on the title-deciding play-offs with the side featuring several rising stars.
But the likes of England wing Henry Arundell could now decide their future lies elsewhere even if a takeover is completed.