Erik ten Hag has urged Manchester United to "strike" in the transfer market if an opportunity arises before Tuesday's deadline.
United have so far added only loan striker Wout Weghorst in January with sources telling ESPN the club are instead focused on strengthening the squad in the summer.
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But with just days to go before the deadline, Ten Hag has put pressure on the board to keep pursuing new signings ahead of what could be a busy second half of the season in four competitions.
"In the coming days, if we had the opportunity I would go for it but that's not also up to me, that's also clear," Ten Hag said, speaking ahead of United's FA Cup tie against Reading on Saturday.(3 p.m. ET, stream live on ESPN+).
"I think this club always has to have the approach that every day you have to get better so if there are opportunities to get better then you have to strike.
"That's my approach so I'm looking around, to research but I have an idea with which profiles we could strengthen the squad."
United are the only English team left in four competitions and Ten Hag is keen to have a squad big enough to cope with the demands of a season that could stretch to more than 60 games.
Interest from West Ham in defender Harry Maguire has been rebuffed and Ten Hag has insisted the United captain remains an important player.
The England centre-back has only started two league games since August and has seen Luke Shaw, usually a left-back, picked ahead of him since the World Cup.
"He's not fifth choice but it's up to him," Ten Hag said.
"I have to say he's training very well, bringing quality and that is what I expect from all the players in the squad. He has to fight for his position and things can change, sometimes also really quickly. I think he is making progress and it's up to him.
"After the World Cup he should have played but then he got ill. I can't do anything about that and he knows that.
"Then you come in a run and he has to wait for his chance, I think those are the laws of football, from top football, from selection. Then you have to wait for a change and in the meanwhile make sure you are ready if the chance is there."
One player who could be leaving Old Trafford is Phil Jones. The defender hasn't played all season because of injury and is out of contract in the summer.
"[The decision] is not taken [that he will leave] until now, the decision about that is for the summer, but for the whole season he's injured," Ten Hag said.
"What I can say is that he's not available for training since the first day of training this season so I think there's not an opportunity for you to recover quickly and be available quickly."