"Maybe there are other players a bit older but we don't think we could win a World Cup with them in the future and would rather invest time and show belief in young players".
"Alexander-Arnold, at right-back, has played really well and for me deserves to be in the squad".
Uncapped Alexander-Arnold is the youngest after an wonderful breakthrough season with Liverpool, which will culminate in next week's Champions League final against Real Madrid.
"We're trying to change the style of play, we have our young players developing with better technical ability with the ball".
Meanwhile, speaking after the announcement of the squad, Southgate told reporters: "I believe this is a squad which we can be excited about".
Southgate's England squad is the third youngest ever for a World Cup, behind only 1958 and 2006. It's a dream come true! "Thank you for all your kind messages!"
Southgate was unimpressed with Wilshere’s fitness
Chelsea's out-on-loan midfielder Ruben Loftus-Cheek, 22, was also given a seat on the plane to Russian Federation after impressing for Crystal Palace this season.
The inclusion of versatile players like Alexander-Arnold, Ashley Young and Fabian Delph, who can all play in defense and midfield, provides options for Southgate, who has tinkered with 4-3-3, 3-4-3 and 3-5-2 formations.
England have enjoyed great success at youth level in recent years, winning the Under-17 and Under-20 World Cups plus the European Under-19 Championship.
England will play two matches before travelling to Russian Federation on June 2 against Nigeria at Wembley and on June 7 against Costa Rica at Elland Road.
England kick-off their group stage campaign against Tunisia in Volgograd on at 7pm on 18 June, before facing Panama on 24 June and Belgium on 28 June.More news: Black American bishop to preside at royal wedding
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