Ulster Unionist MP Danny Kinahan had apologised for posing for a picture at a bonfire with an Irish tricolour placed on top of it - and posting it on Twitter.
The South Antrim MP posted the picture to promote a charity donation by the Ladyhill bonfire organisers.
The picture also showed the placard on the bonfire which states: "No funding, no culture erosion, no surrender."
Mr Kinahan told the BBC he accepted it had been an error in judgement in posting the picture, but said the flag did not go up in flames as it was removed before the bonfire was lit.
He said: "It was an error of judgement and I have apologised to those there.
"The flag was removed before the bonfire was set alight, perhaps I should have had it taken down before the picture was taken.
"What I wanted to get across was here was a family, rural bonfire scene and they'd raised £600 for meningitis.
"They were having fun and this is Protestant culture - let's recognise each other's cultures and get on with it. "
The picture remains on Mr Kinahan's Twitter.
Well done Ladyhill Bonfire Group .. Donation to Meningitis NI .. & great turnout from families and local groups pic.twitter.com/tsQug6nPp5— Danny Kinahan (@DdeBK) July 11, 2016