Newcastle owner Mike Ashley already has the naming rights over Ibrox Stadium

Newcastle owner Mike Ashley has been confirmed as the buyer of 4.26m shares in Rangers International Football Club, more than doubling his stake.

to French bank BNP Paribas, but an announcement to the Stock Exchange revealed that the transaction was completed on Ashley's behalf.

The £850,000 purchase of shares means he now holds an 8.92% stake in RIFC.

But he is limited to no more than 10% by an agreement with the Scottish FA.

The governing body has a rule that no individual holds stakes in two clubs, but compromised, while applying limitations, when Ashley was brought into RIFC as a shareholder by previous chief executive Charles Green.

BBC Scotland's Chris McLaughlin "There has been much talk of Mike Ashley selling Newcastle but he has said recently that he is going nowhere until the end of next season at the earliest. It does appear he is turning his attention further north, though. He is now the second largest shareholder with just under 9%. He already owns the naming rights to Ibrox and has the deal to sell the shirts. This is Ashley making his move to have influence at boardroom level."

Ashley, who is now the second largest shareholder in RIFC behind Laxey Partners who hold 16%, declined to buy shares in the open offer made to existing shareholders last month.

His stake was then diluted to 3.69%, but the stake he bought from Hargreave Hale, at 20p per share, was larger than the number of shares he could have bought in the open offer.

The BBC has also learned that during negotiations to provide a loan to the club last month, which would have prevented the need to hold the open offer, Ashley sought control of Rangers' trademark rights. This was declined by the directors, although a company called Rangers Retail Rights Limited was incorporated on 9 September 2014, with Ashley among the three directors.

If Ashley had participated in the open offer, the club would have received around £840,000, but instead he spent a little more than £850,000 buying Hargreave Hale's shares. The Rangers board are currently trying to raise funds, with RIFC unlikely to be able to pay December's wages.

Ashley also announced last month that he will not consider selling Newcastle until the end of next season at least. This is expected to remain the case, unless an offer substantially higher than the club's market value is received.

Former Rangers director Dave King wants a controlling stake at Ibrox

While the SFA has its own rules on dual ownership, the Premier League in England does not. The Football League does, though, along with Uefa, which means that if Ashley sought to increase his stake further - by challenging the SFA's stance in the courts - and Newcastle were relegated, or both Newcastle and Rangers qualified for Europe in future seasons, he would face further problems.

If Ashley did seek to raise his stake in Rangers, particularly if he was presented as the only viable option to the club's funding crisis, the SFA board would need to vote on the matter. Ashley is not the sole possible solution, though, since Dave King and investors aligned with the former Rangers director want to invest in RIFC in return for a controlling stake.

The Englishman already owns the naming rights of Ibrox Stadium and a commercial agreement over the club's retail sales through his Sports Direct company. The Sons of Struth fan group has already raised the prospect of boycotting his stores to try to persuade him to rescind the naming rights agreement.