Manchester United manager Louis van Gaal admitted the club have taken a backwards step with their fifth-placed finish this season, but he said he can help them challenge for the title in the next campaign.

Speaking after United ended the league season with a 3-1 home win against Bournemouth, Van Gaal bemoaned his club’s luck during the campaign and praised their fans, while admitting that the team needs to improve offensively.

At the end of the game, the United manager had addressed the supporters on the pitch and thanked them for their “unconditional backing.”

Van Gaal said he was disappointed to miss out on qualifying for next season’s Champions League, but said all judgement about his future should wait until after Saturday’s FA Cup final against Crystal Palace.

“We didn’t reach our aim. We have to qualify for the Champions League,” he told the BBC. “We have still the FA Cup final to go. Everyone has to make up his mind at how we have done this season at that time.

“I can only say I have a contract of three years and I want to fulfill that. The transition period is not over yet. I am still the manager.”

Asked in his news conference if he will be at Old Trafford next season, Van Gaal replied: “Yes, because I have signed a three-year contract.”

After being questioned on whether this campaign’s finishing position represented a backward step, he replied: “Of course. Our aim in the first year, the second year and the third year was the Champions League. That’s the highest level.

“A club like Manchester United has to play at that level, but there are more clubs who want to play in the Champions League.

“A title challenge is always possible — because Leicester City was more or less a relegation team. But in sport, you have to show it and fight for it.

“You need luck and I cannot say that we had a lot of luck this season, but that is not the only reason. We didn’t create too much. Defensively we are one of the best teams in the Premier League but attacking-wise we have to improve.”

Speaking about what he said to the fans on the pitch, Van Gaal added: “I have said that with very much conscience. They have showed, in spite of the fact that we have not always played very well, that they have supported the players on the pitch always.

“However things have gone on the pitch, they never let us down and they always have come, 75,000, always. Not today, but why do you think [after Sunday’s security scare caused an abandonment]?

“I had 11 guests for nothing coming from the Netherlands [on Sunday] then I went to a restaurant, Mr Wing’s, to receive my guests instead. We have a lot of fans from Asia who could not come back and see the match.”

Despite this being an impressive campaign defensively, United conceded a late goal. That meant that the club’s player of the season, goalkeeper David De Gea, could not share the Golden Glove with Petr Cech for most clean sheets.

The United manager said: “My irritation is that we conceded a goal because David De Gea is not a winner of the Golden Glove. I have told the players also.”

Looking ahead to Saturday’s FA Cup final against Crystal Palace at Wembley, he said: “It is very much time ago that the club won this cup so it is very important for all of us. I came here to win a title. An FA Cup is a big title in England.”