EU's Competition Commissioner Margrethe Vestager told CNBC that Irish authorities are "taking too long" to get unpaid taxes from Apple.

Speaking to CNBC over the phone on Thursday, Vestager said she hopes Ireland will recover 13 billion euros ($14.46 billion) from Apple "very soon".

The European Commission ruled last August that Ireland had granted undue tax benefits of up to 13 billion euros to Apple. The illegal tax aid has created tensions between Brussels and Dublin, given that the latter doesn't want to be seen as unfriendly to business.

At the time, Apple's CEO Tim Cook said the EU's decision would harm future investment decisions in Europe, but Vestager has downplayed the impact.

"I haven't seen any evidence of that," Vestager told CNBC, mentioning the advantages that companies have when accessing the European market, which has a potential customer base of more than 500 million.