Romanian President Traian Basescu demands PM Calin Popescu Tariceanu to publicly present proof to support his accusations that a group of oligarchs has influence over the Romanian head of state, the Presidency announced in a press release on Thursday.

The announcement was made a day after Basescu engaged in a fierce and unprecedented exchange of accusations between Basescu and Tariceanu, shaking the power-sharing coalition in Bucharest.

On Wednesday, Basescu showed the media a letter sent to him by PM Tariceanu two years ago, in which he is asked to intervene in a judicial case launched against oil mogul Dinu Patriciu, known for his close relationship with the PM.

Also yesterday, Basescu, a Democrat, said it was then that he lost his trust in Liberal Tariceanu but kept the note secret because such a scandal would have threatened Romania’s EU accession efforts at the time. Tariceanu dismissed that the letter, which is unclearly worded, meant what Basescu understood.

But he continued with similar attacks, accusing the president of supporting a group of oligarchs.

Now, Basescu urges PM Tariceanu to “urgently” submit requests to revoke ministers who allegedly operated to support “the so-called groups of interests at the Cotroceni Palace”, the headquarters of the Presidency.

Unless Tariceanu fails to do so, Basescu believes the prime minister’s statements are nothing but smoke aimed at covering his own deeds before the public opinion.

The Presidency intervention comes as Romanian prosecutor-general Laura Codruta Kovesi said on Thursday that her institution was analyzing Tariceanu’s letter to Basescu to see whether there is enough proof to launch an inquiry into the issue.

The scandal was sparked by revelations a former presidential aide made on TV last week. Basescu’s ex-counselor Elena Udrea was the first to speak of the existence of Tariceanu’s letter.