There is mounting pressure on the Chairman of the Dáil spending watchdog to consider resigning his position.

John McGuinness is facing calls from within government and the opposition after he argued while a Junior Minister for spouses to be allowed go on foreign trips and to be paid for by the taxpayer.

Independent TD Finian McGrath is calling on the Public Accounts Committee (PAC) chair to resign.

His comments come after revelations in the Irish Independent which have led another committee member - Simon Harris of Fine Gael - to say that Mr. Guinness needs to consider if the credibility of the spending watchdog is being undermined.

It is reported that the Fianna Fail TD argued the case with civil servants in an e-mail in 2007.

In a tweet Deputy Harris, who is a member of the PAC, says the credibility of the spending watchdog "cannot be undermined and the Chairman needs to consider that".

PAC has a huge & important body of work to do. The credibility of the Committee cannot be undermined and the Chairman needs to consider that

— Simon Harris TD (@SimonHarrisTD) June 10, 2013

However John McGuinness is insisting he has done nothing untoward saying he was only seeking clarification on the matter.

"I have considered it, I don't see any difficulty with it whatsoever; maybe Simon might let me know what his difficulty might be" he said.

"But as far as I'm concerned there was nothing untold here - there was clarification sought, clarification was given, my wife did not travel on the trade mission in question and there was no cost therefore to the State relative to that" he added.

Independent Shane Ross says he had not seen the story but that taxpayers paying for spouses travel should not be allowed. While Deputy McGrath says the position of the Carlow-Kilkenny TD is no longer tenable.

Mattie McGrath and Maureen O'Sullivan have also commented on the latest revelations surrounding Deputy McGuinness.