The Manchester United winger was named in the initial group to play Wales in Swansea on Monday evening, but hasn’t reported for duty at St. George’s Park after ending the campaign on loan at Cardiff City with a niggling injury.
Zaha was one of four players in the squad only due to feature in the Wales game, along with Tom Ince, Danny Ings and Jesse Lingard, who are all too old to feature in the Toulon Tournament in France next week.
Wales U21s v England U21s
UEFA European U21 Championship
Group One Qualifier
7.30pm, Monday 19 May 2014
Liberty Stadium, Swansea City
Live on Sky Sports
And it was decided that it was best for the 21-year-old to rest his injury in order to make a full recovery for next season.
"Wilf has been carrying something and we decided that it was probably best not to aggravate it," revealed head coach Southgate, who had an initial 25 man squad in place for the Wales game before a squad of 20 head out to Toulon after that.
"We would have only had four days with him [Zaha], whereas with the others we get two weeks, which is a great extended period to work with them.
"He would have only been available for the one game anyway, so over the five games, we’ve got Nathan [Redmond] who’s been playing really well and Tom Ince, who were the two wingers who started the last game.
"And there’s Jesse Lingard, who has been knocking on the door for us a lot and has had a really good loan spell at Brighton, and that’s before we look at the boys who have just come into the squad."
Watch England's first training session at SGP on Thursday
The Under-21s will be training at St. George’s Park until Sunday, when they make the journey to South Wales for the game against Geraint Williams' side.
From there, they will head to Toulon on Tuesday after playing the match against Wales in Swansea on Monday evening.
Meanwhile, goalkeeper Sam Johnstone has also withdrawn from the squad and returned to Manchester United. Johnstone reported to St. George's Park on Thursday, but after assessment from the England medical team, has returned to his club for further treatment.