“Don’t hold your breath,” she told reporters in Brussels about the timing of decisions targeting Apple and online shopping giant Amazon.com, whose tax affairs in Luxembourg are also under intense scrutiny.
“I’m just warning you,” she said.
Finance Minister Michael Noonan had previously said a ruling wouldn’t come until after the election.
The two companies are slated to be next in the firing line months after the EU watchdog ordered the Netherlands and Luxembourg to recover as much as €30 million in back taxes from Starbucks and a Fiat Chrysler unit.
While Ms Vestager refuses to be drawn into speculation, analysts say in the Apple case, repayments could potentially dwarf those amounts.
Ms Vestager in January signalled she’s willing to add Google parent Alphabet’s £130m (€168m) tax deal with the UK to her growing list of investigations.
All of the companies cited by the EU say they have done nothing wrong and that any tax arrangements were in line with applicable laws.
Despite saying the next wave of decisions isn’t imminent, Ms Vestager said she won’t wait for the EU courts to decide on pending appeals by Luxembourg, the Netherlands and Fiat against last year’s state aid repayment orders.
“No, we wait for the job being done thoroughly and with the quality that we want it to be done with,” she said.
Ms Vestager last month responded to criticism of the EU state aid probes by US Treasury Secretary Jack Lew.
While the EU’s tax probes have been focusing so far on US companies, including an ongoing investigation into McDonald’s, the commission in January ordered Belgium to recover about €700m in illegal tax breaks given to at least 35 companies, including Anheuser-Busch and BP.
Meanwhile, Apple must pay $450m (€409m) to end an antitrust suit after the US Supreme Court yesterday refused to question a finding the company orchestrated a scheme to raise prices for electronic books.
EU Competition Chief on Apple Tax Probe: ‘Don’t Hold Your Breath’ https://t.co/GKWeIdrPz5 by @rsgnl pic.twitter.com/kOC94seQ5b
— MacRumors.com (@MacRumors) March 7, 2016