It emerged last week that Norwich had rejected an offer for the England U21 international, however Barca are still in contact.
Sport says Aarons has agreed personal terms on a five-year deal with Barcelona, but the two clubs have not reached an agreement yet.
Barça coach Ronald Koeman is a keen admirer of the player and told him as much when he spoke with him last season.
Norwich is asking for a fee of £20m plus a further £10m in add-ons, although sources close to the negotiations admit they would accept less.
Aarons first met Koeman when he was the Netherlands coach. The player was in Norwich's starting line up in a league game against Liverpool last season, with the Barça boss attended. At the end of the match, their paths crossed and Koeman told the youngster how impressed he had been with his potential.