Romania’s prime minister, Victor Ponta, has conceded defeat to opposition centre-right candidate Klaus Iohannis in a surprise result.

Social Democrat Ponta had won in the first round of voting, and was ahead in opinion polls but on the day it was provincial mayor Iohannis who came out on top in the second round runoff.

There had been widespread anger at voting problems overseas which appears to have played against the prime minister.

Winner Iohannis said: “Now, 25 years after the revolution in December 1989, people left their houses to fight for their right to vote.”

Ponta said he accepted the people’s decision but had no plans to resign as prime minister meaning the new president will face a hostile parliamentary majority against him.

“I would like to thank all Romanians who voted, I would like to say that the people are always right. I called Mr. Iohannis and I congratulated him on his victory. I and my colleagues, as long as we are in public positions, will fulfil our duties for the country,” declared Ponta.

Iohannis has promised to tackle corruption and bring about an independent justice system – at the moment the judiciary is under special EU supervision.

Sunday’s turnout was the highest in any Romanian election since 1996.