De Ligt – who is certain to leave Ajax at the end of the season according to head coach Erik ten Hag – is one of the most sought-after defenders in Europe, where Barca are among the clubs reportedly interested.
Barca president Josep Maria Bartomeu refused to rule out a move for the 19-year-old Netherlands international in an interview during the week.
Asked when he would announce his transfer to Barca, De Ligt replied: "Announce? There is nothing to announce."
When the reporter pushed him further, a smiling De Ligt said: "We're in the semi-finals of the Champions League and we're first in the league. That's enough to play for."
The teenage centre-back's midfield team-mate and international compatriot Frenkie de Jong, 21, has already agreed a move to Barcelona at the end of the season, and De Ligt is widely expected to follow in his footsteps.
The Eredivisie side have proven their worth against a clutch of top teams in Europe so far, playing some scintillating football along the way.
De Ligt and Ajax will face either Tottenham or Premier League holders Manchester City in the semi-finals of the competition as they bid to reach the final in Madrid, where a meeting with Barcelona is distinctly possible.
The Catalan giants eased past Manchester United 3-0 at home to record a 4-0 aggregate victory and earn themselves a spot in the last four, where they will face either Porto or Liverpool. The Reds hold a 2-0 advantage from the first leg and are widely expected to advance.