London Irish have filed for administration after being suspended from the Premiership.

Owner Mark Crossan and a US consortium have been unable to reach a deal.

Crossan, who bought the club in 2013, said administration had "always been the last resort" but was now the "safest path forward".

"We bitterly regret the difficulties it will present to each and every one of you," he said in a letter to staff.

"My focus is now on working with the appointed administrator and I hope that the club will come out of administration as quickly as possible."

Crossan said the decision to suspend the club from the Premiership was "bitterly disappointing".

"I understand the sadness felt by the thousands of our loyal supporters and the frustrations of our incredible coaches, medical staff, back-office team, and players," he said.

"This decision has ultimately ended any hope of an acquisition of the club and has regrettably forced us to file for administration."

Despite plans announced in 2021 to expand its top division to 14 teams, English rugby now faces the prospect of a 10-team Premiership next season after the demise of Worcester Warriors and Wasps.

Crossan said he spent the past seven months "working closely" with the Rugby Football Union (RFU), Premiership Rugby (PRL) and representatives of the NUE Equity to "complete a widely publicised deal" to buy club.

He said a deal could not be agreed "despite our very best efforts".

He said he had made "significant financial investment" since buying the club, but that it it is "not feasible for me to continue absorbing the multi-million-pound losses of the club each year, indefinitely".

After Irish's suspension on Tuesday, RFU board chair Tom Ilube said rugby must "professionalise its management off the pitch".

"Covid accelerated the impacts of underlying structural challenges and had a major effect on PRL clubs and the RFU," he said.

"Given the cost-of-living crisis, the post-Covid bounce-back has been weaker than expected, and that has meant clubs with unsustainable business models have gone out of business - regrettably so for players and their fans.

"All three clubs that have failed this season have had fragile business models for many years."

Crossan said Ilube's comments "completely overlook the precarious situation other clubs are currently in".

"Collectively, owners of clubs are working very hard to transform their models, but the lack of real support, at times, is non-existent," Crossan said.

"The professional game in this country needs to be radically transformed."

How did London Irish get here?

While Irish had a solid season on the pitch - they finished fifth and reached the final of the Premiership Rugby Cup for the second successive season - there has been talk for some time of issues off the field.

The club are understood to have debts of about £30m, and Crossan had to step in to pay overdue wages in April, minutes before players were preparing to submit breach-of-contract notices.

The club were given a deadline of 30 May to complete the takeover or risk being suspended from the Premiership next season, but the Rugby Football Union pushed that cut-off point back to 16:00 BST on Tuesday.

As well as completing the takeover or proving they had funding to operate for next season, Irish had to ensure all staff and players were paid in full for May, after only 50% of the money had been forthcoming.

The club were last week served a winding-up petition by HM Revenue & Customs over an unpaid tax bill.

Petitions were filed at the High Court on Friday against London Irish Holdings Limited and London Irish Rugby Football Ground Limited.