Speaking at a press conference to officially present new recruits Shinji Kagawa and Nick Powell, Ferguson admitted that it was always harder to make signings when there was a major tournament taking place.
But he is now looking to strengthen his squad ahead of the new Premier League campaign, when United face the challenge of trying to regain the title they lost to neighbours Manchester City.
"We could possibly bring one, maybe two, more in," said Ferguson.
"When there's a major international tournament on, there's a delay in the transfer market. But now the European Championships are over, we're trying to bring someone in."
Ferguson is delighted to have snapped up Powell from Crewe and Kagawa from Borussia Dortmund, and hopes they will make an impact for the club.
He said: "We've always done well in terms of getting players at the end of season, instead of waiting all summer.
"In Kagawa's case, there was a fair bit of negotiating and that kept going for weeks. As for Powell, we knew Dario Gradi [Crewe Alexandra director of football] would help us do the deal quickly."
Discussing Powell's best position, Ferguson added: "I asked Dario if Nick could be a central midfielder. Dario thinks that's his position and Nick does too so we're all in accord. We hope he'll be a central midfield player and that's where we'll develop him."
Ferguson is excited about the sort of impression Kagawa could make in his debut season, having helped Dortmund win the Double in Germany last term.
"He'll play further forward [than Powell]. We shouldn't be looking at one player changing the way we play but he could make a difference," said Ferguson.
"He can give us that extra in the final third of the field. If his goalscoring record continues he could be a very good player for us."
With UEFA's Financial Fair Play rules now in force, and an increasing onus on home grown talent, Powell's arrival ticks a few boxes, in addition to bringing the promise of increased longevity.
"It is always better if you get the best English players," said Ferguson.
"You never know how football is going to change in terms of regulations for a start and it could be that home based players become very important."
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Ferguson confirmed he had spoken to old friend and Crewe director of football Dario Gradi about Powell, who will be part of United's first-team squad this season, and they, together with the player himself, believe the teenager can be of most value in a central midfield role, rather than the advanced position he occupied last season.
United had sealed the transfer prior to last term's play-offs, which has proved to be an astute piece of business given Powell's brilliant Wembley winner against Gillingham.
However, whilst he accepts the step up he is being asked to make could hardly be greater, Powell is approaching his task with relish.
"It is a whole different world," he said.
"At Crewe it is one camera and one person. At Manchester United it is the whole world.
"Crewe to Manchester United is the biggest step and I still have a lot of developing to do.
"But I am hoping to achieve what everyone expects me to achieve. I want to be a Manchester United player."