According to Sky sources, Palace have agreed a fee with West Ham for Sakho understood to be between £10m and £12m.
Roy Hodgson is keeping "quiet" Crystal Palace's linked move for Diafra Sakho but says the club are "working overtime" on signings.
The Senegal international is yet to start a Premier League game for the Hammers this season, scoring four goals in the 17 games he has featured in this term.
Whilst the 28-year-old has been a reliable servant to West Ham, the aforementioned figure would represent fantastic business for the club, and would allow David Moyes to strengthen in other areas of his squad. However, the English tactician insisted on not giving updates on their pursuit of the former Metz striker. There is bound to be conflicting reports.
Moyes has plenty of other forward options including Andy Carroll, Javier Hernandez and Andre Ayew, and the Scot should easily be able to cope without Sakho, especially considering the peripheral role he has played recently.
Sakho has now been given permission to hold talks with Palace and undergo a medical at Selhurst Park.
The Hammers squad is incredibly imbalanced, and the addition of a central midfielder and centre-back will be Moyes' priority this month.
Sakho is expected to cost around £10million although the fee may increase with add-ons.