The Sinn Féin member says his contact with a witness "was inappropriate, ill-advised and wrong"
Mick Wallace says the resignation of the chair of the North's finance committee will have no effect on investigations into NAMA.
Sinn Féin MLA Daithí McKay resigned his seat and been suspended from the party after allegations regarding a witness, who made claims of impropriety against former First Minister Peter Robinson.
It is claimed he gave advice to a blogger who claimed Mr Robinson benefited financially from the sale of NAMA assets.
In a statement yesterday, Sinn Féin Chief Whip Carál Ní Chuilín said: "Daithí McKay has resigned as MLA for North Antrim with immediate effect and has been suspended from Sinn Féin."
While Sinn Féin's Martin McGuinness said the party did not have any knowledge of any alleged contact with witnesses appearing before the inquiry.
Mr McGuinness said: "If the allegations of inappropriate contact prove to be true, then Daithí McKay needs to seriously consider his position as an MLA."
"I want to state categorically that I had absolutely no knowledge of this exchange or contact. And having spoken to all relevant personnel in the Assembly I am now entirely satisfied that Sinn Féin had no knowledge of any such contact," he added.
While in a personal statement released to the media, Mr McKay said: “Having reflected on the allegations against me which have arisen in the last 24 hours, and consulted with associates, friends and family, I acknowledge and accept that my contact with a witness to the Finance & Personnel Committee’s NAMA inquiry in advance of his testimony was inappropriate, ill-advised and wrong."
"I apologise wholeheartedly for this."
Independent Wexford TD Mick Wallace says this will change nothing about the NAMA investigation.
"It doesn't actually change anything around the NAMA issue - it's really sort of an internal political issue up there," he told Newstalk Brekafast.
"I'm sure pressure will come on Sinn Féin from the opposition parties in Northern Ireland, but I don't see it having an impact on any investigations into NAMA."
"The finance committee in the North is very much like our own PAC...it didn't actually unearth anything anyway."
"What it did do was is probably air the issue, and it was effective in doing that - but there wasn't really any findings from their deliberations so it doesn't have any impact really on the questions around the workings of NAMA."
"I don't see it impacting whatsoever on that."