The Scots begin their Pool C campaign on Friday 10 June with a tie against South Africa in Padova, before moving on to nearby Treviso to tackle England on Tuesday 14 June. Their final group fixture sees them face Ireland in Rovigo on Saturday 18 June, with their remaining two tournament matches dependent on performance in the pool phase.
Scotland U20 coach Peter Wright said: "It’s great to be able to call on someone like Duncan Weir.
“He has a number of excellent attributes: his ability to control games, his confidence, and his experience not just of this tournament but of Magners League rugby and the Scotland A set-up which he broke into last November.
“He’s the sort of player who will keep the scoreboard ticking over and keep you in contention, and I know the boys are delighted to have him in the fold.”
Scotland squad
Backs: Sam Atkin (Edinburgh Accies), Mark Bennett (Glasgow Warriors/Ayr), Glenn Bryce (Heriot’s), Michael Doneghan (Glasgow Warriors/Stirling County), Danny Gilmour (Stirling County), Stuart Edwards (Stirling County), Kerr Gossman (Glasgow Warriors/Glasgow Hawks), Stuart Hogg (Glasgow Warriors/Hawick), Craig Jackson (Melrose), Sean Kennedy (Stirling County), Jamie Stevenson (Westcombe Park), Duncan Weir (Glasgow Warriors).
Forwards: Alex Allan (Loughborough University), David Cherry (Team Northumbria), Mitch Eadie (Filton College), Richard Ferguson (Melrose), Robin Hislop (Edinburgh/Boroughmuir), George Hunter (Glasgow Warriors/Glasgow Hawks), Robert McAlpine (West of Scotland), Colin Phillips (Edinburgh/Stewart's Melville), Grant Runciman (Melrose), Alex Spence (Heriot’s), Jamie Swanson (Boroughmuir), Mitchell Todd (Nottingham), James Tyas (Bath), Hamish Watson (Leicester Tigers)