The midfielder made his England debut against Italy in March and he was hopeful of securing a place in Gareth Southgate’s final 23-man squad, which was named on Wednesday.
However, he has missed the cut with midfielder’s Dele Alli, Eric Dier, Jordan Henderson, Jesse Lingard, Ruben Loftus-Cheek all preferred instead.
Cook, who is joined by Adam Lallana, Jake Livermore, Tom Heaton and James Tarkowski on the standby list, may still get a chance to head to Russia but only at the expense of one of his compatriots.
England boss Gareth Southgate said: ‘History tells us that one of those standby players may end up in the squad, as it’s very unusual for us to get through the end of the season and our two preparation games without any issues.
‘All of the guys on standby have been really professional in their approach to this. They recognise there’s still an opportunity and we’ve had a lot of conversations over a period of time with them about their situation.’
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