SINN Féin MP Chris Hazzard said "plenty of people" from across the community have visited his South Down constituency office in a building named after two IRA men.
The politician has come under criticism for moving his office to the McNulty-Magorrian, with the son of an IRA victim accusing the centre of "glorifying" paramilitaries.
The building in Castlewellan is named after Peter McNulty and Paul Magorrian.
McNulty (47) was killed in January 1972 when a bomb he was placing outside the town's RUC station exploded prematurely, while Magorrian (21) was shot dead by the British army in disputed circumstances in the St Malachy's estate in Castlewellan in August 1974.
Mr Hazzard said on BBC Radio Ulster's `Talkback' it was "absolutely fitting" to open his office there, adding it had been named after the men before he was born.
He rejected an accusation by DUP assembly member Jim Wells that it was a "sickening insult", branding the unionist politician a "hypocrite".
"They were killed in their area and their families are held in the highest regard," he said.
"I would also point out that less than 50 metres from this office there is a British war memorial to remember all those that gave their lives in a British uniform, some of whom in that uniform killed Paul Magorrian who was killed beside my office by a British soldier.
"We have a place in Castlewellan where the British army are remembered and our Irish republican dead are remembered."
Mr Hazzard said his move would not put people off using his constituency service.
"I have no doubt in the society we live in there would be people who would have trouble engaging with me simply because I am a Sinn Fein representative. Likewise there will be people who find it difficult to deal with a DUP representative. That is the type of society we come from."
The row comes after DUP South Belfast MP Emma Little-Pengelly was criticised for hosting a constituency advice service in a band hall linked to UDA men Joe Bratty and Raymond Elder.
Ballynafeigh Band Hall has been a "focal point" for an annual march commemorating them.
Yesterday she wrote on social media: "Apprentice Boys Halls or Band Halls are simply not comparable to references to terrorism. The comparison is deeply offensive to many within Unionism.
"It must be noted - I have a full time advice centre, offer house calls, range of local venues etc. Always options for constituent."
