All 12 English Premiership clubs have issued a joint statement to insist there is no conspiracy to prevent promotion to the top flight.

Rotherham failed to earn promotion last season as reward for winning the National League One title due to problems with their home ground. Worcester chairman Cecil Duckworth claimed recently the top flight clubs were attempting to prevent the South Yorkshire club taking their place in the Premiership again, despite moving to Rotherham United's Millmoor ground.

Duckworth claimed Premiership clubs offered a financial incentive to Rotherham to remain in the second division this season - and are planning to hatch a similar deal with the champions elect.

The English Rugby Football Union announced an investigation into the claims yesterday.

The RFU had previously said it was confident the normal process of one club promoted taking the place of one relegated club would be respected this season. But after meeting with representatives of the Premiership clubs, it decided that an inquiry was warranted.