United moved in when Barcelona refused to pay the Dutchman's agent £12million to broker a move to the Nou Camp, after De Ligt led his Amsterdam club to a league and cup double.
Manchester City are also back in the frame for the 19-year-old.
But sources in Holland last night suggested United have moved into pole position after agreeing to outbid any club and meet Mino Raiola's demands for a £350,000-a-week wage and a huge fixer's fee.
De Ligt, who has been named Holland's footballer of the year, looked destined to join Ajax team-mate Frenkie de Jong at Barca. But the Catalans are refusing to do business on Raiola's terms.