The EU executive will decide in "days or weeks" whether to legally challenge Hungary's controversial constitutional reforms if they breach EU laws and treaties, an EU spokesman said.
"Our concerns remain and will remain until the (European) Commission has completed its legal assessment of these new laws" adopted by the Budapest parliament last week, Commission spokesman Olivier Bailly told a news conference.
"The College (of commissioners) will decide in the coming days or weeks when or if there is an infringement, and of course the Commission will act in order to make sure that the Hungarian law is in line with EU treaties."
With the college of 27 commissioners due to meet on January 11, legal experts in the Commission were poring over official translations of the reform bills to see if they were compatible with EU law and basic EU values.
Once the analysis is over, the Commission "will decide on the next step," Bailly added.
After tens of thousands of Hungarians poured into the street to protest Prime Minister Viktor Orban's reforms, Brussels has been under pressure to determine whether the new constitution, as its detractors say, undermines vital checks and balances on the power of the centre-right government.
Adopted thanks to a two-thirds parliamentary majority enjoyed by Orban's Fidesz party, critics say it tightens his grip on state bodies meant to be independent, including the judiciary and the central bank.
Bailly said the Commission had been the first to express its concerns over the planned reforms and went into lengthy detail on potential infringement proceedings should Budapest have failed to take EU notifications into account.
Infringement proceedings, which can include action before the European Court of Justice as well as fines, would take several months if initiated.
In December, the Commission and the International Monetary Fund broke off preliminary talks on a financial aid package of between 15 and 20 billion euros ($20-25 billion).
Brussels also called Wednesday on the Hungarian authorities to respect media pluralism after the country's sole opposition radio, Klubradio, had its broadcasting licence withdrawn in December.
A high-level group set up in the aftermath of criticism over Hungary's new media laws in early 2011 is to meet on January 25, with Hungary on the agenda, a Commission official said.
Neelie Kroes, the Digital Agenda Commissioner, "encourages the Hungarian government to consider issuing additional radio licences" and "hopes that any non-successful bidders from recent and future bidding processes will find success as internet radio stations."