The Egyptian was in the stands at Wigan on Wednesday night and Southgate is hoping he can provide the spark which his side are so badly lacking after opening with two Premier League defeats.
Southgate said: "Mido has had his medical, he's agreed everything and was here tonight.
"We've just got to tie up things now and it's important to keep trying to strengthen the squad. We've got to perform as a team but we didn't do that tonight.
"We weren't positive until after they scored and we've got to pick ourselves up now for Saturday."