By Razvan Scortea
BBC News, Bucharest
Romania is in the grip of a political storm as relations between President Traian Basescu and his prime minister hit rock bottom.
The very public split threatens the ruling coalition
He has accused Prime Minister Calin Popescu Tariceanu of trying to influence a criminal investigation on behalf of a close associate.
The president said the PM was acting for shadowy business groups.
The PM hit back, accusing President Basescu of trying to undermine his government and destroy his party.
In a dramatic televised statement on Wednesday, Mr Basescu produced a note sent to him in 2005, in which Mr Tariceanu asked him "to have a word with the prosecutors" investigating the affairs of his friend and political ally, Dinu Patriciu.
At the time Mr Patriciu was running one of the country's largest oil companies. He is accused of tax evasion and improper share dealings.
The president said that the moment he received the note, he lost all trust in the prime minister.
Basescu promised a new leadership style when he won the 2004 election
Mr Basescu said he had not spoken out earlier because he feared he might jeopardise Romania's accession negotiations with the EU.
Mr Tariceanu admitted sending the note, but argued that he simply wanted the president to ensure the investigation proceeded correctly.
He went on to accuse the president of undermining his government, and of being at the centre of a web of dubious business deals involving state contracts.
The country's chief prosecutor said the note might theoretically represent an act of corruption, and all details would be checked out.
The row exposes deepening tensions between the main partners in the ruling centre-right coalition - the pro-presidential Democrats and the Liberals who support the prime minister.
As the president does not have the authority to sack the prime minister, the government's fate will be decided by parliament.
The main opposition Social Democratic party has already called for the impeachment of Mr Basescu and the removal of Mr Tariceanu.
Meanwhile, the Democratic Party is considering its options, withdrawal from government being one of them.
If that happens it will scupper Mr Tariceanu's premiership.