The European Union executive launched legal action against Hungary Tuesday over contested reforms of its judiciary, central bank and data protection authority.

"We have just decided to launch infringement proceedings" against Hungary on three points, said European Commission president Jose Manuel Barroso.

"We do not want a shadow of doubt on respect for democratic principles and values to remain over the country any longer," he added.

The 27-member Commission, which was meeting in Strasbourg, had been widely expected to issue three letters of warning to Prime Minister Viktor Orban's government, demanding it scrap the incriminated reforms or face infringement proceedings.

An EU official said Budapest was being given one month to row back on legislation widely seen as threatening the independence of its central bank as well as the judicial system and its data protection authority.

"We'll use all our powers to make sure that Hungary complies with the rules of the EU," Barroso said last week.

Anger over legislation adopted December 31 sent tens of thousands of Hungarians on to the streets in protest this month, while causing the suspension of talks with the EU and IMF to secure a credit line of up to 20 billion euros ($25 billion) for the cash-strapped nation.