"The RFU has concluded that the players leaving their Covid-secure environment on October 20 without then isolating from the rest of the group on their return has resulted in the bubble environment being compromised, with the potential risk of Covid transmission from individuals outside the bubble to everyone in the Barbarians team and management.
"The RFU is therefore left with no alternative but to cancel the game."
Robshaw and Saracens halfback Richard Wigglesworth, two senior members of the squad thought to be involved in the breach on Wednesday evening, accepted blame for their part in the incident with remorseful tweets on Saturday morning, shortly after official confirmation that the game had been scrapped.
Robshaw explained that he had left the biosecure environment after a training session, while Wigglesworth said that he was "embarrassed and beyond gutted" to have let down Barbarians head coach Vern Cotter and the RFU.
RFU chief executive Bill Sweeney admitted to feeling "incredibly frustrated and disappointed" with the outcome.
"We are incredibly disappointed to be calling a halt to this fixture, we know how much fans were looking forward to seeing the teams play," he said.
"However, our priority is to protect the health and safety of the England squad and the other international teams they will go up against this autumn.
"There has been a great deal of effort put into Covid codes of conduct and planning for games, including cooperation with Premiership clubs to release additional players to fulfil the fixture safely, and we are all incredibly frustrated and disappointed that the actions of a number of Barbarians players mean we no longer feel it is safe for the game to go ahead."