According to Premier League chief executive Richard Scudamore a “small but significant number of agents” have refused to co-operate with the inquiry.

Therefore, the Premier League will formally ask the Football Association for a joint inquiry as English football’s governing body have the powers to require agents to disclose information which may be essential to complete any investigation.

The 17 transfers being investigated further represent a small proportion of the 362 that fell under the Quest inquiry’s terms of reference but Scudamore felt it was important Stevens was given more time to determine their probity.

“When the Premier League first initiated this inquiry into alleged irregular payments we made it clear we wanted a thorough and exhaustive investigation,” said Scudamore.

“It is manifest that this investigation has been carried out meticulously, professionally and independently.

“To that end the inquiry, as originally instigated under its specific terms of reference, is effectively complete.

“However, Lord Stevens has satisfied himself as to the probity of all but 17 transfers out of the 362 that fell under the inquiry terms of reference.

“This is ostensibly because of the failure of a small but significant number of agents’ refusal to co-operate with the inquiry.

“The [Premier League] board has decided to ask Lord Stevens to make further investigations into these 17 transfers, under a new mandate and terms of reference.

“We have also decided to formally ask the FA to make this a joint inquiry as they are vested with the powers to require agents to disclose, as well as providing the direct interface with FIFA, which will be essential to complete any investigation.”

Scudamore also said the Premier League, their member clubs and the FA would all be studying the observations and recommendations concerning the administration and governance of transfers recommended by Lord Stevens before deciding what course of action to take.

Lord Stevens stressed all of his 38 recommendations must be adopted to safeguard the integrity of the game.

“Every one of these recommendations must be implemented as they are essential to the future and reputation of this game,” he told a news conference, televised live by Sky.

“Failure to so will result in the game remaining under attack and its remaining members subject to allegations and innuendo.”

Lord Stevens criticised the lack of assistance he had received from some agents during the course of his team’s investigation.

“Agents failure to respond has resulted in delays to this inquiry,” he added. “We will be providing the Premier League with a number of incidences where mandated processes have not been followed.

“The frequency of these instances show the clubs neither anticipate nor are concerned by the strictures imposed by the FA.

“It is my view this further erodes the reputation of the game and those involved in it. Such scant disregard for the rules and regulations of this great game is unacceptable.”

Stevens added a body must handle the audit of transfers rather than the FA.

Lord Stevens revealed "eight major agents" had not co-operated but he refused to identify the people involved.

“This is no witch hunt. This is no whitewash,” he said. “The reason why we are not naming names is the inquiry is ongoing. I know you would like us to name and shame but I can’t do it at the present stage.

“The game, in relation to the majority of what we have seen, is clean but the accounting processes and monitoring of the clubs is in a mess.”

Scudamore added: “People will only be named when there is evidence which will lead to a charge. The concentration is now on a number of agents and other parties – not clubs and club officials. In one sense they (clubs) are in the clear in that the investigation into them has finished.

“The whole purpose of this inquiry is to not only bring forward any evidence but bring forward recommendations for how processes and practices can be improved.

“We have employed one of the most senior ex-policemen in the country whose credibility is beyond reproach and has found what he has found. We always said we had no pre-judgment what the outcome would be.”