The Eurostadium in Brussels was due to host four group matches and one Last 16 game, but it won't be ready in time so those matches have been reassigned to Wembley Stadium in London.
With delays to the construction of a proposed stadium in the Belgian city of Brussels, UEFA has made the decision to move the group-stage matches that were originally set for Belgium to Wembley Stadium, as well as a Round-of-16 matchup.
However, UEFA opted for Wembley, which has already been chosen as the venue for the semi-finals and final.
A draw was also held on Thursday to decide which cities would host games from the various groups.
The 2020 tournament is the first to be played under a new format with group games spread across several countries.
"We received a letter yesterday that 31st of January there will be a final decision but the decision - yes or no - they don't know".
The company contracted to build the stadium in the northern suburb of Grimbergen, BTP Ghelamco, said they were able to build the 60,000-capacity Eurostadium in 18 months, but the Flanders region in which it will be situated has yet to issue a building permit.
"Missing out on Euro 2020 does not necessarily mean a death blow for our stadium plans", he said. "If the answer had been no, it would have been a problem for us to find a new stadium".
UEFA said Russian Federation and Ukraine would be kept apart in the group stage, as would Armenia and Azerbaijan.
UEFA has previously indicated that qualified nations that are home to one of the 12 host cities would be assigned to that group - meaning Spain and Ireland would be automatically paired up.
The Welsh FA (FAW) said in a statement that it was "extremely disappointed" with the outcome.
The Olimpico will also host one of the Quarter-Finals.