Romanian Prime Minister Marcel Ciolacu announced his resignation on Monday.

His decision comes after his coalition government's presidential candidate was eliminated in the first round of elections on Sunday.

"We saw how Romanians voted yesterday which means that the ruling coalition has no legitimacy, at least in this formula," he told reporters after a meeting of his Social Democrats party.

Hard-right populist leader George Simion won the most votes, 40.5%, in the first round of the presidential election, a rerun of the original vote from last year. He will face off against pro-EU Bucharest mayor Nicusor Dan in the May 18 runoff who received a 20.9% share of the vote.

The governing coalition's candidate, Crin Antonescu, managed to secure 20.3% of the ballots cast.

Political turmoil deepens in Romania

Ciolacu also pushed his Social Democratic party to exit the governing coalition.

"We saw how Romanians voted yesterday (Sunday), which means that the ruling coalition has no legitimacy, at least in this formula," he added.

The Social Democrats had formed a coalition government with the centrist Liberals and ethnic Hungarian UDMR to help keep the European Union and NATO state on a pro-Western course. 

Without the party, a governing majority can only be formed with the support of the far-right in the legislature.

"This coalition is no longer legitimate," Ciolacu told reporters.

"The next president was going to replace me anyway, that's what I've read."

Simion alligned with Trump, opposes aid for Ukraine

The original presidential vote last year was canceled because of widespread concerns over Russian interference in favor of far-right Calin Georgescu, who has been placed under investigation and has been barred from running for office.

Georgescu ally, Simion, who is 38 years old, opposes military aid to neighboring Ukraine and is critical of European Union leadership.

Simion says he's aligned with US President Donald Trump's "Make America Great Again" movement and appears to be riding a similar wave of popular anger in the European Union and NATO member country of Romania.

US Vice President JD Vance said the cancellation of last year's vote indicates Romania does not share American values, while Elon Musk referred to the chief judge of the country's top court as a "tyrant."

With some 19 million people, Romania is the most populous country in southeast Europe and the most important EU and NATO member in the region.

A Simion victory in the May 18 runoff would increase the number of eurosceptic leaders in the EU, which already includes Hungary's Viktor Orban and Slovakia's Robert Fico.

Edited by: Darko Janjevic