Romania's most powerful politician, Liviu Dragnea, was jeered by jubilant protesters on Monday as he was taken to jail after a corruption conviction was upheld by the country's top court.

Crowds shouted "go to prison!" as the strongman was taken from his Bucharest home to begin a three-and-a-half year sentence.

It was another blow for for the Social Democratic Party leader, who was snubbed by voters in both the European elections and an anti-corruption referendum held on the same day.

"With this decision, the Liviu Dragnea era ends," said opposition politician Dan Barna. "Romania is getting better."

One protester waved a pair of handcuffs in front of Dragnea's face, another threw a roll of toilet paper at his car as it entered the prison. Later, others gathered in Bucharest's Victory Square to celebrate the court ruling.

Dragnea, who is also the speaker of the lower house of parliament, was convicted last June for having two party workers paid by a public agency for fake jobs. He appealed, but the conviction was upheld on Monday.

He was already barred from being Romania's prime minister because of a 2016 conviction for vote-rigging.

Since coming to power in late 2016, the Social Democrats have steadily chipped away at the independence of the judiciary, raising sharp criticism from the European Union and triggering Romania’s largest street protests in decades.

Voters on Sunday overwhelmingly backed a referendum called by centrist President Klaus Iohannis to prevent Dragnea’s party from further weakening the courts.

Tens of thousands of Romanian diaspora were unable to vote on Sunday after queuing for hours outside embassies and polling stations.

Romania is ranked one of the most corrupt members of the EU by Transparency International.

The country has been rocked over the last two years by protests at what campaigners claim are politicians’ attempts to decriminalise some corruption offences and weaken the judiciary.

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