The prosecutors are targeting Ponta's activities from 2007-2011 when he was working as a lawyer and a lawmaker, and also suspect him of conflict of interest while serving as prime minister.
But after today's parliamentary vote, which saw 231 against and 120 in favour of waiving the premier's immunity, the anti-corruption agency DNA will not be able to continue with its investigation into the charges of conflict of interest.
The result was unsurprising given the domination of Ponta's centre-left coalition, but drew anger from his political rival, conservative President Klaus Iohannis, who repeated his call for the premier's resignation.
"The parliamentary majority refuses to accept the signal given by the citizens" who want "a stop to corruption, politics conducted with integrity and responsibility", said the statement from Iohannis, who was elected in November after a campaign centred on fighting corruption.
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The DNA prosecutors announced Friday that they had launched a probe into the social democrat premier over suspected money laundering and tax evasion, sending one of the EU's poorest country into a political crisis.
Ponta, 42, has refused to step down over the allegations and said the case has been orchestrated by the opposition, adding that a criminal case against him would be "equivalent to a coup d'etat".
He is accused of receiving the equivalent of around 55,000 euros (about USD 61,000) when he was a lawyer from his political ally Dan Sova, a member of parliament suspected by prosecutors of abuse of power in three cases but who has maintained his parliamentary immunity.
This probe is the latest in a string of anti-corruption enquiries carried out by the powerful DNA, probes that have led to several influential Romanians losing their jobs over the past months.
"I want to appear before the prosecutor to present my point of view... It is in my interest to move forward and I am confident that this matter will be clarified," he said, nevertheless describing the opening of the probe as an "error".
The US embassy in Bucharest today issued its first statement since the political crisis erupted.
"Any allegations of wrongdoing by government officials should be fully investigated without interference, and the law should be applied equally to everyone," it said, adding that it would not comment on individual cases.