Sinn Féin TD Martin Browne has apologised for old Facebook posts linking to conspiracy theories about 9/11 and for sharing content comparing the US to the Nazis.
Mr Browne said the posts from 2014, 2015 and 2017, when he was a Sinn Féin councillor in Tipperary, "do not reflect my views".
"I apologise for these posts and I should not have posted them," he said in a statement.
Among the examples was one from 2015, when Mr Browne shared a post that suggested a hologram of a plane was used to fake the Twin Towers attacks on September 11, 2001.
"It would make you wonder," he wrote.
In another post, from 2014, he shared a link to a Russia Today story in which the late Cuban president Fidel Castro was quoted comparing Nato to the Nazi SS and criticising the US and Israel for creating Islamic State.
"He may not be wrong," Mr Browne wrote.
Earlier, he was accused of trying to censor an Oireach- tas committee after a failed bid to move its meeting into a private session to dis- cuss controversial remarks he had made on local radio.
The chair of the Oireachtas Petitions Committee was confronted by Fine Gael TDs over comments he made on Tipp FM on Wednesday, when he admitted calling to party members' homes when he had disagreed with their social media posts.
In the same interview, Mr Browne said Sinn Féin needs to stop apologising for its "core belief" that Provisional IRA attacks were a continuation of the War of Independence.
Speaking on Tipp Today in relation to the Brian Stanley tweet row, he said: "Apologies, in my own personal view, they should stop."
The remarks drew criticism from Fine Gael committee members.
The meeting was forced to adjourn after calls from Fine Gael and Fianna Fáil for Mr Browne to make a Dáil statement on his comments.
Deputy government whip Brendan Griffin said he was "very concerned" by the comments and asked Mr Browne to commit to making a statement in the Dáil on the matter.
Mr Browne insisted the issue was not on the agenda and urged members to listen to the full radio interview.