The Albion star has been in impressive form this season, with coach Darren Moore describing him as ‘incredible’ last weekend.
Livermore’s form was enough to impress Southgate as he continually selected him in his squad this season.
However, he has failed to make the 23-man squad but Southgate still wants him on the fringe of things.
Livermore earned a Premier League player of the month nomination for April, after his performances against Liverpool and Tottenham and he could be selected if any of the squad become unavailable.
He joins Tom Heaton, James Tarkowski, Lewis Cook and Adam Lallana in being placed on the back-up list. They will train with the squad ahead of the tournament before they travel to Russia in June.
Watford defender Sebastian Prodl will face world class opposition from Russia, Brazil and Germany after being called up by Austria.
Huddersfield have lost out to Premier League rivals Brighton for the free transfer signing of Mainz's Nigerian defender Leon Balogun.
Jean Michael Seri will be allowed to leave Nice in the summer transfer window, president Jean-Pierre Rivere has confirmed.
Captain Marek Hamsik has admitted that he could leave Napoli this summer as he has been linked with a big-money move to China.