It followed a meeting of senior officers last night.
The Derry branch of Comhaltas had appealed against the decision of the organisation's Ulster Council not to put the city forward as host.
A decision on whether the city will host 2013's event will now take place this weekend.
At a meeting of Derry Comhaltas last Wednesday, members voted 13-1 in favour of the bid.
However, after two dissident republican bombs exploded in the city last week, the Ulster council turned down the bid.
Comhaltas promotes traditional Irish music and culture around the world.
On Sunday, the organisation's Ulster council said it was impossible to support the city's bid to host the popular music and dance festival because of the danger from dissident violence.
It said that with "deep regret and long consideration", it was turning down the bid because safety was paramount.
The UK City of Culture organisers had been hoping to bring the Fleadh to Northern Ireland for the first time ever in 2013.
But the UK link to the traditional Irish event had already proved a stumbling block with some members.
Director general of Comhaltas nationally, Labhras O Murchu said: "There was a meeting again with the same body who met last Saturday.
"They reconsidered the decision which was made and we're expecting an application to arrive on Wednesday.
"It's impossible at this stage to call what way the vote may go.
"Because this issue has been so well debated there isn't a member on the council who hasn't a greater understanding of the issues involved in the Derry bid."
Eibhlin Ni Dochairtaigh, chair of the the Derry City branch of Comhaltas, welcomed the move.
"I think that whatever issues and concerns were expressed have been addressed to their satisfaction.
"I very much appreciate and welcome their continued support. The reversed decision has ratified the bid."
Sinn Fein MLA Martina Anderson said: "This follows two days of intensive discussions.
"The reassurance that some of the members needed has been given. I'm delighted the application will progress. There is still a lot of work to do.
"There was a massive ground swell of support nationally and internationally for Derry."
The central council of Comhaltas will meet on Saturday for a final decision on the venue. Sligo and Ennis are also bidding to host the fleadh
BBC News - Derry Fleadh bid to go ahead after decision reversed