The Three Lions meet up at St. George's Park on Sunday evening to begin their preparations for the games, which see England face Lithuania in Kaunas on Friday 5 September (5pm BST) before heading on to Tiraspol and a match against Moldova on Tuesday 9 September (5pm BST).
And Southgate has handed a first Under-21s call to both Manchester United defender Tyler Blackett and Tottenham Hotspur winger Alex Pritchard, who is currently on a season-long loan with Championship side Brentford.
Both players have been previously capped, with Blackett featuring at U16, U17, U18 and U19 level before making his Premier League debut this month under Louis Van Gaal, after impressing with United in pre-season.
Pritchard was part of the Young Lions squad for last summer's U20s World Cup under Peter Taylor.
There are also places in the squad for the likes of Everton left-back Luke Garbutt, Brighton & Hove Albion midfielder Jake Forster-Caskey and Fulham striker Cauley Woodrow, who all featured under Southgate in the Toulon Tournament in France earlier this summer.
The rest of Southgate's group is made up of players who had helped England to the top of their qualifying group table with their performances last season.
Goalkeepers: Jonathan Bond (Watford), Jack Butland (Stoke City).
Defenders: Tyler Blackett (Manchester United), Eric Dier (Tottenham Hotspur), Luke Garbutt (Everton), Michael Keane (Manchester United), Jamaal Lascelles (Newcastle United, on loan to Nottingham Forest), Liam Moore (Leicester City), Jack Robinson (Queens Park Rangers, on loan to Huddersfield Town).
Midfielders: Tom Carroll (Tottenham Hotspur, on loan to Swansea City), Nathaniel Chalobah (Chelsea), Jake Forster-Caskey (Brighton & Hove Albion), Will Hughes (Derby County), James Ward-Prowse (Southampton).
Forwards: Saido Berahino (West Bromwich Albion), Tom Ince (Hull City), Danny Ings (Burnley), Harry Kane (Tottenham Hotspur), Alex Pritchard (Tottenham Hotspur, on loan at Brentford), Nathan Redmond (Norwich City), Cauley Woodrow (Fulham).