Newall told lutonfc.com: "We tried to get Gary McSheffrey permanently but that has not been possible yet, it may take a bit of time. We have made an offer but it is not up to Coventry's valuation so we couldn't reach an agreement at this stage.
"He wants to play games, which is understandable and at this point another month's loan is not what Gary is after but we think that he may consider a permanent move.
"We are happy with what he did last year and what he has done this season and we would like to sign him."