A Stormont scrutiny committee has called on the North's Finance Minister to stand aside pending the outcome of a probe into a party colleague's backchannel contact with an inquiry witness.
Máirtín Ó Muilleoir has so far resisted pressure to temporarily step down in the wake of the controversy that forced the resignation of Daithí McKay, a former Sinn Féin chairman of the Assembly's Finance Committee.
That committee broke from summer recess to hold an emergency session on Tuesday to discuss the furore around Mr McKay's handling of its inquiry into allegations of impropriety around the North's largest ever property deal.
Mr McKay apologised and quit as an Assembly member last week after admitting "inappropriate" communication with loyalist blogger Jamie Bryson ahead of his appearance before the committee.
Private messages were exchanged between Mr Bryson and the Twitter accounts of Mr McKay and Sinn Féin party worker Thomas O'Hara. Both republicans have been suspended by Sinn Féin.
The contacts were made before the loyalist made explosive claims to the finance committee about the efforts of the National Asset Management Agency (Nama) to sell its huge Northern Ireland portfolio to US investors.
Mr Bryson went before the committee to allege that former Democratic Unionist leader Peter Robinson was set to benefit from the £1.2bn (€1.38bn) transaction - a claim the then Democratic Unionist first minister vehemently denied.
The Twitter messages published in the press last week made reference to Mr O Muilleoir - then a member of the finance committee - indicating how he might intervene during the evidence session involving Mr Bryson.
While Mr Ó Muilleoir has insisted he had no knowledge of the backchannel, and Sinn Féin Deputy First Minister Martin McGuinness has given him his full backing, during Tuesday's hastily convened committee hearing a number of members questioned the Finance Minister's denials.
A majority of members voted to send a letter to the minister asking him to stand down from his ministerial role while an investigation by the Assembly's Commissioner for Standards takes place.
The sole Sinn Féin member present at the hearing - Caitriona Ruane - voted against the move.
DUP committee chair Emma Pengelly said the minister should temporarily leave office to ensure public confidence.
"Any request for the Finance Minister to step aside is not a judgement as to whether he is guilty of any allegation," she said.
Mrs Pengelly added: "Ultimately this is a request for him to step aside from the committee - it will be a decision for him. I think there is much for him to reflect on."
The committee also agreed to call Mr Ó Muilleoir to come before members to answer questions.
The 2014 deal between Nama and US investment giant Cerberus has been dogged by controversy after €8m linked to it was found in an Isle of Man bank account.
Critics have claimed the arrangement included multimillion-euro fixer fees.
Nama was established in the Republic of Ireland at the height of the financial crisis to take property-linked loans off the books of bailed-out banks.
It sold 800 Northern Ireland-based property loans to Cerberus, a multibillion-euro fund.
All parties involved in the transaction have denied wrongdoing.