Rangers owner Craig Whyte is facing probes from the SFA and the police as he insists there was "no criminal wrong-doing" in his conduct at the club.
Mr Whyte confirmed that he will not be attending the club’s home game against Kilmarnock on Saturday as he takes a "step back" from Rangers until the end of the administration period.
Strathclyde Police was handed a dossier on the "ongoing situation" at Rangers, which officers are currently examining the information.
However, the Scottish Football Association has announced a formal investigation of Rangers, citing: "The Scottish FA’s previous efforts in obtaining information relevant to the fit and proper person requirement has been restricted by the club's solicitors' continued failure to share information in a timely or detailed manner."
Rangers' administrators welcomed the move, while Craig Whyte insisted he had nothing to fear from the investigation.
Joint administrator Paul Clark said: “We welcome the announcement by the SFA and believe it will be in the best interests of Rangers and Scottish football.
“As administrators of the Club we will co-operate fully with such an inquiry, subject to the terms of reference, and have indicated this to the SFA."
The SFA statement continued: "We are concerned by the developing situation at the club and the new information that has come to light since the appointment of the club administrators, Duff and Phelps. The chairman and his panel will be briefed by the chief executive, Stewart Regan, next week and will consult further with the administrators, Duff and Phelps, as part of their inquiry."
Stewart Regan, SFA chief executive, said on Friday that the association had not received the "detailed information" it had requested regarding Mr Whyte, who took over the club last May.
He continued: "We feel we have no option but to appoint an independent committee to investigate a number of concerns we have raised.
"We expect the investigation to be concluded as quickly as possible and will confirm the outcome in due course. We will be making no further comment on the investigation in the meantime.
"Finally, I would like to reiterate the need to learn the lessons from this unedifying episode. It is essential that we work together to improve the overall sustainability and competitiveness of the game in this country. This is a matter that the Scottish FA is already in discussions with the relevant league bodies to address."
Mr Whyte, who flew to London the night Rangers went into administration and has not returned, responded to calls for a Crown Office investigation into his takeover stating there was "no criminal wrong-doing whatsoever."
STV understands Rangers officials had been advised by Strathclyde Police that the owner should not attend Saturday’s SPL match over security concerns. The police force refused to comment on the issue.
In his statement, Mr Whyte said: "The decision to call in the administrators was painful but it was the right thing to do. They have promised to publish a full report as soon as possible and I very much welcome that.
"In spite of the endless speculation and attempts at character assassination by certain sections of the media, I am 100% confident that the administrators' report will prove that every penny that has come in and gone out of Rangers has been properly accounted for. And I wish to state categorically for the record now that I personally have not taken a single penny out of Rangers since I became chairman and have paid all my expenses from my own funds."
Former Rangers chairman Alastair Johnston said on Thursday night that he had contacted the Crown Office to investigate whether any criminal activity had taken place in the takeover of the club last May.
In response, Mr Whyte said: "I have absolutely nothing to fear because any fair investigation will prove that I have always acted in the best interests of Rangers and been involved in no criminal wrong-doing whatsoever."
In the statement published on the club’s website, the owner said: "While the administrators get on with their work, it is only right that they are given the time and space they require to complete their task. That is why I have decided to take a step back from events so that I do not become a distraction to either that process or to Ally McCoist and the players.
"Regrettably, I will not be attending tomorrow's match against Kilmarnock. Although I would dearly love to be at Ibrox for the game, my priority is, and will continue to be, to assist the administrators in any way I can to bring this process to as speedy a conclusion as possible."
Administrators Duff and Phelps said Mr Whyte’s announcement brought "further stability" to the club.
Meanwhile, Mr Whyte’s representatives said on Friday that a writ had been served on the BBC over a documentary and subsequent reports he had carried on the Rangers owner.
The action is over claims made in a documentary broadcast last October, as well as more recent reports by the corporation on Mr Whyte’s business history.
A BBC Scotland spokesman said: "We can confirm we have received a writ from Mr Whyte. We stand by our journalism, all of the allegations made, and will defend any action vigorously."
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