The former Villa boss does not believe adding faces in January is the answer to their problems.
The Villans are currently rooted to the bottom of the Premier League table, with just seven points from 17 games.
That leaves them ten points from safety, with Newcastle United, who they drew 1-1 with on Saturday afternoon, currently sitting in 17th place on 17 points.
They are expected to be busy in the January transfer window with Garde looking to add experience to his relatively young side, but O’Neill says he must look to turn things around with the squad he already has.
“Naturally it’s disappointing for a club like Aston Villa,” he told Sky Sports. "It’s disappointing to see them in the position they are in now.
“If there’s money available in January then that’s great, but I think you have to look at what you have.
“It’s really important to galvanise this squad because even if you get two or three players in, it might take a little bit of time and that’s something that’s running out for Villa.”
While Aston Villa may been keen to add players to the squad in January, doing so is likely to prove a difficult task.
With the situation as it is, relegation is looking almost a certainty this season, meaning a move to Villa Park is not exactly an attractive one at present.
It is also notoriously difficult to do good business in the winter window, with teams not keen to sell for the majority of the time.
Both are likely to leave Garde frustrated come the end of January, and perhaps focusing on working with what he has is the best route forward for him.