Arsenal manager Arsene Wenger insists he will delve into the transfer market only if the right player becomes available and will resist the temptation to make a signing to satisfy supporters' demands.
Wenger admits Arsenal would benefit from a top-quality addition in the closing hours of the winter window, but refuses to be pressurised into recruiting a player who would cause the club a problem and hamper the development of young talent.
"I have to be strong enough to resist," said Wenger, who was speaking ahead of his side's Premier League clash with Liverpool.
"What is important is that you bring in players who can strengthen your team, or you do nothing, you're strong enough to do nothing.
"We could do with top quality, one more, but you have to find him.
"If I bring a normal player in, I give the club a problem.
"It is for four years and I am stopping the young players to give him a chance. The second thing is even more damaging because we have two or three young players with a good chance to play for us."
Former England captain David Beckham has begun training at Arsenal's Hertfordshire training base, but Wenger played down the prospect of a permanent move and would not confirm an interest in Spain striker David Villa, saying only that Barcelona do not wish to sell.
Wenger, who is happy with his forward options, added: "It doesn't go away, but Barcelona doesn't want to sell David Villa. They have made that very, very clear.
"As numbers we have enough. We have plenty of quality strikers."
Wenger does not believe there is room to negotiate with Barcelona.
"You respect the desire (to keep a player)," he said. "If I say that somebody is not for transfer I expect the other clubs not to try to buy him."
The prospect of Beckham signing for Arsenal is not under consideration, Wenger insists.
The 37-year-old former England captain is currently without a club after leaving Los Angeles Galaxy at the end of the Major League Soccer season and has told Wenger he has not trained since.
"That is not on the agenda," Wenger said.
"If, in his mind, he wanted to play in the Premier League he would not have gone on holiday.
"He would have prepared and come in and tried to impress me. He told me he has done nothing at all.
"He asked to come here to get fit. (It's) purely for fitness. There's no speculation about signing or anything.
"Maybe in June he has plans to play somewhere."