Sakho, who has scored six goals in as many starts for West Ham, last played for Senegal in a friendly against Kosovo last May but has since been overlooked by Giresse.
Sakho said: "When I signed for West Ham, he [Giresse] phoned me and said that as I was changing clubs he will want to see how it goes.
"But then I started scoring goal after goal and many people in Senegal asked for my call-up.
"I didn't hear from him. It is a lack of courage."
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