Southern calls for RMT posters to be destroyed
Southern has asked for posters asking passengers to contact the union over ongoing rail strikes to be "removed and destroyed", it has emerged.
The firm came under fire following a tweet urging people to message the RMT.
Commuters criticised the company but the union said staff were being "attacked and assaulted" as a result of the campaign.
In a leaked email seen by the BBC, Southern said the request had caused "extremely negative sentiment".
Its subject line read: "***URGENT*** Southern RMT Strike Poster - Cancel print job and remove from display".
The memo added: "Due to extremely negative public sentiment around the brand it has been decided to cancel this poster campaign."
It instructed staff to "ensure all copies of the posters are removed from display and destroyed immediately".
'Badly thought out'
The RMT has said it believed the advert amounted to "targeted harassment".
In a letter to Southern bosses, general secretary Mick Cash said operator Govia Thameslink Rail (GTR) was breaching its duty of care to staff.
"GTR has fed the passengers and public a line that railway staff working for GTR are to blame for the sorry mess that is Southern Rail.
"RMT hold you and your company wholly responsible for violent and threatening situations that arise for your employees whilst at work, as a result of the badly thought out campaign.
"Any harm will be on your hands."
Southern said press adverts would continue but posters at stations would be taken down.
The operator said: "Feelings were running high after day one of the campaign and we decided, having taken on board comments from some passengers, not to display the posters at stations.
"We make no apologies for this campaign - our aim was to get the debate going."
Months of industrial action by the RMT and high levels of staff sickness have hit Southern's services, which link London with Surrey, Sussex, Kent and Hampshire.
RMT members have voted to accept a deal with ScotRail to settle a dispute over the role of guards on trains.
The union said it hoped the deal would provide a model for resolving the row with Southern.
Analysis, Tom Edwards, BBC London transport correspondent
Many have viewed Southern's ad campaign attacking the RMT as a huge, bizarre PR gaffe.
In the leaked email, the firm admits the posters have caused "extremely negative public sentiment around the brand".
But it seems inconceivable Southern wouldn't have been aware of the response they'd get. Their Twitter feeds are often full of criticism.
And the company's bullish response - that they make no apologies for the campaign - makes you think this is really about reinforcing their message.