Tony Pulis plans to strengthen Crystal Palace's squad and backroom staff in a bid to help the Eagles stay up.
Celtic boss Neil Lennon has refused to name his transfer targets but confirmed he is looking to strengthen his team.
Defenders Titus Bramble and Matt Kilgallon are in the final months of their current agreements, and Bramble has consistently said he would like to stay.
The centre-half is back in favour and has started 10 games in succession, but with Sunderland in a fight for Premier League survival his future will remain unclear until the summer.
O'Neill told the Sunderland Echo: "Now, at this minute, the most important issue is trying to get points on the board. I know it's a cliche, but those things can wait."
Sunderland have taken just two points from a possible 18 and go into this weekend's game against Norwich just six points above the bottom three.
O'Neill's side face a daunting run of fixtures post-Norwich as they take on Manchester United, Chelsea and Everton either side of a derby at Newcastle.