Onana has been West Ham’s target all summer and they have a deal in place to sign the midfielder from Lille.
The Hammers have agreed to pay a fee of €35m and another €5m in potential add-ons, but they are yet to agree on personal terms.
Everton are now favourites to sign him after tabling a bid comparable to that West Ham have put in and the midfielder would prefer a move to Goodison Park.
And it has been claimed West Ham are now circumspect about signing Onana in the ongoing transfer window.
Everton have the edge in the race but West Ham were still believed to be pushing to sign him this summer.
But it has been claimed that West Ham are now dithering over taking the next steps in trying to sign Onana.
It remains to be seen whether West Ham will try to push through with a deal or allow Everton a clear run at the 20-year-old this summer.