Players linked with Liverpool, Everton and Arsenal are likely to be in action in Group C's games.
Ibrox side Rangers have reportedly failed to reach an agreement with manager Mark Warburton over a new contract.
Hal Robson-Kanu snatched a late winner as Chris Coleman's side beat Slovakia 2-1 in their first-ever match at a European Championship finals.
Roy Hodgson's side conceded an injury-time equaliser as they began their Euro 2016 campaign with a 1-1 draw in Marseille.
The Arsenal striker scored France's opening goal in the 2-1 win over Romania.
Ibrox side Rangers will compete with Old Firm rivals Celtic in the Scottish Premiership next season.
Tottenham Hotspur's Premier League title hopes went up in smoke at Stamford Bridge.
Goals from Gareth Bale and substitute Hal Robson-Kanu saw Chris Coleman's side begin their Euro 2016 campaign with a 2-1 win in Bordeaux.
Here he comes. There was a cheer of expectation from the other end of the Stade de Bordeaux, where the Dragons had their den, as Gareth Bale walked across from the left.
Thirty years they have waited and now Robert Lewandowski stands before them, yet Michael O’Neill has urged Northern Ireland to embrace their European Championship bow and insisted there is nothing to fear against Poland on Sunday.