The Welsh striker was released from the club when he was convicted in April 2012 and was released from prison last month after serving half of his five-year sentence.
There has been much speculation surrounding the future of Evans, with the club denying reports that he had been offered a contract at Bramall Lane.
On Tuesday, United released a statement explaining that they had acceded to a request from the PFA (Professional Footballers' Association) to allow Evans to return to training, although the League One outfit are yet to decide if they will re-sign him.
"The club acknowledges receipt of a request from the Professional Footballers' Association to the effect that the club consider allowing Mr Evans, who is a PFA member, to train at the club's facilities," the statement read.
"According to the request, this training would be with a view to enabling Mr Evans to get back to a level of fitness, which might enable him to find employment in his chosen trade.
"This request has come to the club, because it is the last club at which Mr Evans was registered before his conviction.
"While some have speculated about whether the club will or should invite Mr Evans to return to SUFC as a registered footballer, the club is not prepared at this time to decide that issue."
