Birmingham City’s owners explore moving into rugby union and buying Prem franchise

• RFU due to confirm shake-up of rugby's top division

• Knighthead Capital Management in early discussions

Birmingham City's owner, Knighthead Capital Management, is among a number of American investors exploring the purchase of potential new franchises in Prem Rugby before a radical shake-up of the sport due to be ratified by the Rugby Football Union on Friday.

The RFU council will vote at Twickenham on proposals to ringfence the 10-team Prem with no promotion or relegation until 2030, when a staged expansion is planned, beginning with the addition of two more teams.