The on-loan winger had the opportunity to join the England squad for the tournament in South Korea but has decided to remain in Glasgow so he can be part of Celtic’s remaining league matches and the cup final against Aberdeen on 27 May.
Roberts told the Celtic website: “I have enjoyed my time with Celtic immensely and from day one at the club it has felt like home. It is a special place and it has been a privilege to be part of the success we have enjoyed.
“We have had a brilliant season so far and in such a special year for the club I want to be part of everything here. It is a once in a lifetime opportunity and now I will focus on continuing to do all I can for Celtic.
“I spoke to the gaffer and this is just something I really wanted to do.
“I have a great relationship with everyone around the England squad and I wish all the other lads and the management and backroom team the very best for the World Cup in South Korea.”
Celtic will win the domestic treble if they beat Aberdeen at Hampden.
Roberts’ loan deal from Manchester City is due to expire at the end of the season but Celtic manager Brendan Rodgers has not given up hope of keeping the player.