The 22-year-old has been on loan at the Stadium of Light since last summer and, after impressing boss Steve Bruce, the club have contacted Egyptian Premier League side ENPPI to exercise the option to sign him permanently.
Elmohamady has made 19 appearances for the Black Cats and Bruce feels that, although the versatile player is still adapting to English football, there is still a lot more to come from the wide man.
"Ahmed has been a pleasure to have around the place since he joined us," said Bruce.
"He's a great professional, has settled into the club and is keen to learn.
"He is adapting well to the unique demands of the Premier League and I'm certain there's still much more to come from him."
With no Premier League fixture this weekend, Bruce has arranged a practice match to give some of his players a run-out in their quest to return from injury.
After enduring a three-month spell on the sidelines with a back injury, Lee Cattermole will feature and the Black Cats boss hopes the skipper will be fit for next Saturday's sell-out meeting with Liverpool at the Stadium of Light.
Nedum Onuoha, Boudewijn Zenden, Danny Welbeck and Fraizer Campbell will also be involved as they step up their comebacks from injury.
Cattermole hasn't featured since the home defeat to Blackpool in December after a troublesome back injury failed to clear up.
Bruce handed the 22-year-old an extended break in a bid to aid his recovery and, despite fears he may have missed the rest of the season, the captain could be back sooner rather than later.
That will give Bruce a massive boost as he prepares his side for the rest of the season, and with a top ten finish still his top priority, the manager believes the return of Cattermole could give his side a huge lift.
"We're having a practice game on Saturday morning, just for all the players who are coming back," Bruce explained.
"That includes Nedum, Zenden, Cattermole of course and Welbeck. Campbell came through half an hour against West Ham on Tuesday, so all of a sudden, we're a bit better in terms of numbers, which is great for us, in the run-in especially.
"We're not concerned about Cattermole long-term. Thankfully, he's flying and he's happy with his back.
"He got a knee in the back and tried to run it off, but it wouldn't get any better. He was diagnosed with severe bone bruising and if he had kept playing with it, it was so fragile that it could have turned into a stress fracture. That was the last thing we wanted.
"Catts has just been unfortunate up here. Just when he was starting, he's been out for about three months.
"When you look at us when he's in the team, he's got an infectious enthusiasm about him, which rubs off on a few others.
"Especially away from home, you need people who can dig a bit.
"Hopefully he could be back for the Liverpool game. He'll play in this game on Saturday then there's a game on Thursday against Manchester United, although that's at Altrincham and the pitch isn't the best. So we'll see how he is."
If the returning players come through today's practice match unscathed, Bruce will have almost a full squad available for the visit of Kenny Dalglish's side next Saturday, with goalkeeper Craig Gordon the only long-term absentee.
Gordon returned from Sweden on Wednesday with the good news that he doesn't require surgery on his knee injury.
Instead he will undergo a month-long programme of special exercises to try and eradicate the problem.
However, if the problem persists, Bruce is worried Gordon will eventually have to go under the knife, which could see his number one out for anything between four weeks and six months.
The Scotland international has 18 months left on his current contract, with talks over an extension not expected to take place until the end of the season.