This is Shaw's first U21 call-up, having previously been capped by England at under-16 and under-17 level.
The 17-year-old has made 18 appearances for Southampton this season and pledged his long-term future to the Club last month having made a big impression at First Team level.
Clyne, meanwhile, already has four Under-21 caps to his name and will hope to take his recent good domestic form onto the international stage.
The duo will link up with the Three Lions after this weekend's game at Wigan Athletic ahead of the game at the Banks's Stadium in Walsall next Tuesday.
They will then return to Southampton in time to prepare for our game against Barclays Premier League champions Manchester City on Saturday 9th February.