The Rugby Football Union has launched an investigation into the breach of coronavirus protocols by a group of Barbarians players that has placed Sunday's match against England in doubt.

A group of around 12 players – known to include Chris Robshaw, Richard Wigglesworth and Sean Maitland – left the team hotel in central London on Wednesday night to have dinner.

It it is understood that the RFU has already begun looking into the breach with a view to summoning anyone at fault before an independent disciplinary panel under the catch-all charge of bringing the game into disrepute.

A deadline of 3pm has been set for the Barbarians to scramble together a matchday 23, and in their desperation the invitational club have recruited two players from the second tier of Welsh rugby.

Cardiff RFC have confirmed that full-back Ioan Davies and centre Max Llewellyn, Wales Under-20 internationals who have only a handful of appearances for the Blues between them, have been drafted into the squad for Twickenham.

England's team announcement for a match that is to act as a warm-up for next weekend's critical Six Nations clash with Italy has been postponed until Friday afternoon – if the Barbarians succeed in finding enough players.