BUCHAREST (Reuters) - Romanian Prime Minister Sorin Grindeanu refused to resign after his ruling Social Democrat Party (PSD) withdrew its support for his cabinet late on Wednesday, contributing to the political infighting in the European Union’s fastest growing economy.

FILE PHOTO: Romanian Prime Minister Sorin Grindeanu speaks as he delivers joint statements with his Israeli counterpart Benjamin Netanyahu in Jerusalem May 4, 2017. REUTERS/Abir Sultan/Pool

The PSD completed a performance review of Grindeanu’s six-month old cabinet on Wednesday evening and found it had failed to uphold an ambitious governing program that had won the party a sweeping election victory in December and a comfortable parliament majority.

PSD leader Liviu Dragnea, who holds tight control over his party, said all cabinet ministers have filed their resignations and that his party was ready to nominate another premier and government together with junior coalition partner ALDE.

“I think it is important that this country benefit from this governing program that Romanians massively voted for,” he told reporters.

But Prime Minister Grindeanu said the review was a surprise and showed his cabinet had failed to enforce measures which had deadlines of 2018 or later, as well as some that could not be implemented, such as bolstering economic relations with Russia, which would be difficult given sanctions imposed by the EU.

“I have tried to understand why ... there is such fury in getting rid of your own government after not even six months,” Grindeanu told reporters. “I don’t see another answer other than ... one man’s desire of holding all the power.”

He said he would only resign after center-right President Klaus Iohannis held consultations with parliamentary parties and indicated he would appoint a replacement from the PSD.

“I want PSD to stay in government,” Grindeanu said. “I don’t want to risk it. At this moment all options are open.”

With Grindeanu’s refusal to resign, the ruling coalition must file a no-confidence vote in parliament to topple the prime minister and consequently nominate a replacement.

Under Romanian law, the president must endorse a premier after consultations with political parties. The appointee then needs to secure a vote of confidence from parliament, where PSD and ALDE control a comfortable majority.

Either way, there would be more delays in policymaking in the EU’s second-poorest state, which has massive healthcare and transport infrastructure needs.

Sergiu Miscoiu, a political science professor at Babes-Bolyai University, said there would be “no gain here for the Social Democrats - the party will see a huge loss of image, or what was left of it.

“The PSD’s great advantage was unity and its capacity to mobilize, vertical decisions and discipline. These myths are gone now. To the extent that Grindeanu will resign, he will throw the ball into President [Klaus] Iohannis’s court, who could appoint a technocrat,” Miscoiu said.

Romania was the EU’s fastest-growing economy in the first quarter, expanding by 5.7 percent, and its budget ran a small surplus at the end of April.

The legacy of Grindeanu’s government also includes a failed attempt at the start of the year to decriminalize several corruption offences, a move foiled by the largest street protests in Romania since the 1989 fall of its communist regime.