Sinn Féin's deputy leader has said the decision to suspend MP Barry McElduff was the appropriate and proportionate action to take following what she described as "a very crass and stupid tweet".
The MP for West Tyrone posted a video on social media with a Kingsmill brand sliced pan on his head on the anniversary of the massacre of the same name.
Relatives of the victims of the 1976 shooting described his actions as callous and offensive.
Speaking on RTÉ's News at One, Mary Lou McDonald said Mr McElduff is contrite, has taken full responsibility for his actions and has been disciplined by the party.
She said that she did not defend his actions but she knew Mr McElduff was not a malicious person and she did not believe he set out to deliberately hurt anyone.
However, she added it was unforgivable to cause pain or hurt to a victim.
She said that Sinn Féin remains hopeful that progress can be made in re-establishing power-sharing but was standing firm on its commitments.
Ms McDonald said Sinn Féin was a "party of dialogue" and had not taken any red line issues in talks, but wanted to see commitments honoured.
These issues were not, she said, nationalist issues but issues that cut right across society.
Meanwhile, Ms McDonald said she could not predict who might run against her to replace Gerry Adams as party leader.
Nominations for his replacement opened yesterday and will close on 19 January.
Ms McDonald said she did not presume she had a "divine right" to replace him but she was hopeful that she would be elected.