Restaurant chain Wagamama has apologised after staff were threatened with disciplinary action if they called in sick over the Christmas period.
A note on a rota at a London branch of the restaurant said it was up to members of staff to get colleagues to cover for them if they could not come into work, adding: "Calling in sick during the next 2 weeks will result in disciplinary action being taken."
In a string of tweets, the chain said it was an "isolated incident" and was "strictly not company employment policy".
They stressed that the notice was the actions of one manager and that they "sincerely apologised for what has happened".
The picture of the rota from the North Finchley branch provoked outraged online after it was shared by Unite Hospitality, a division of the UK's largest trade union, Unite.
Some Twitter users hit out at the rota as an "absolute disgrace", while others said they would "not be eating at Wagamama" again.
Others called for the restaurant chain to take "responsibility" for what had happened "and train your managers better".
However, Brian Simpson, a spokesperson for Unite Hospitality said he feared the incident was not a one-off.
"To threaten workers with disciplinary action for being sick is not just morally reprehensible, it may be unlawful under the Health & Safety act and Equality Act as it discriminates against those with long-term physical and mental health conditions," Mr Simpson said.
He continued: "Although this is an extreme example, we do believe that the issue of sick staff being pressured to come into work is systematic across the company.
"We have heard from workers across the country that conditions have gotten worse and worse.
"We want to sit down with senior managers and see how we can improve conditions."
Unite Hospitality is currently running a campaign to ensure hospitality staff proper rest breaks, paid transport past midnight and a minimum hour contract.
It is also campaigning for the living wage, equal pay for young workers and a campaign to get employers to implement a proper anti-sexual harassment policy.