Leary removed a Facebook post complaining it was "pretty rude of this government not to invite me" to the announcement of the $2 million funding for an extension to the tunnel trail.
She was "grateful" to get an invite from the local organisers, but took issue with not receiving an invitation directly from the government.
Leary told the Otago Daily Times she was sensitive to the fact the event was supposed to be celebratory and her post was becoming a distraction.
"I wanted to ensure that it wasn't a distraction and so I chose to remove the post."
She acknowledged she was invited by the local committee and there was "a miscommunication in my office".
"It's a misstep, I own that.
"It was silly to go on social media about it and I won't do it again.
"My point was that it was unusual not to be invited [by the government] to an event like that."
Two further stages are then planned and, once complete, the cycle and walking trail will span 15km from Mosgiel to Dunedin. It will traverse various tunnels, including two historic railway tunnels.
Upston and members of the community, including Dunedin Tunnels Trail Trust trustees, met on part of the trail on Friday to celebrate the funding.
In her Facebook post Leary wrote it was "pretty rude of this government not to invite me as the local MP as a way of National trying to take the credit for something that [Trust chair] Brent Irving and locals have worked so hard for!"
However, emails obtained showed her office had corresponded she would not be able to attend.
Leary said she was on an international flight and communications went from her office of which she did not have oversight while flying.
Ms Upston said last week’s announcement was great for Dunedin and for an outstanding community group.
‘‘As a local MP, Ingrid was invited in the usual way and I would have welcomed seeing her there.
‘‘It’s a shame Ingrid and her office chose to decline the official invitation, and I’m still not clear why."
