Despite holding talks with officials representing the Super Eagles, Abraham has opted to pledge his worldwide allegiance to England who has he played for at Under-18, Under-19 and Under-21 level.
Abraham, who is on loan at Swansea, received his first call-up along with his Chelsea club-mate Ruben Loftus-Cheek, now on loan at Crystal Palace, and Liverpool defender Joe Gomez.
Speaking about the uncapped trio, Southgate told reporters: "If I'm asking club managers to be fearless and pick young players, I think I've got to do the same".
Abraham, who has also been courted by Nigeria, has scored five goals in 13 appearances at Swansea this season.
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"We have some injuries, but the players who are fit are well capable of putting a good performance in on Saturday".
Loftus-Cheek, 21, has played seven games for Palace, while 20-year-old Gomez has become Liverpool manager Jurgen Klopp's first-choice pick at right-back for Premier League games.
Southgate's men booked their place in the tournament last month and he will use the friendlies as a chance to experiment with his squad.
" It's very pleasing news to see someone we've brought to the club on loan rewarded with his first call-up".
Dunk, 25, and March, 23, have earned plaudits following Brighton's impressive start to the Premier League season.