(ANSA) - Rome, March 17 - European Justice Commissioner Viviane Reding on Monday rejected ex-premier Silvio Berlusconi's bid to run in the May European Parliament elections at the top of his Forza Italia (FI) party's candidate list. Italy's centre-right opposition leader Berlusconi, who was banned from running for office in Italy or Europe because of a tax-fraud conviction late last year, has been appealing his conviction to the European Court of Human Rights.

The ruling last year marked the first definitive conviction for Berlusconi, 77, after more than 20 years of legal battles against magistrates who he says are left-wing and biased against him.

He has not accepted the tax conviction and has insisted he intends to stand for election in the voting May 22-25 for the European Parliament.

That won't be happening, warned Reding.

"I will not go into laws at the national level. But European law is very clear on this," Reding said, driving home the point that Berlusconi will not be eligible to stand for the continent's vote.

Her remarks came at the same time that her department within the European Commission released a report complaining that Italy's much-criticized snail-paced justice system became even slower in the period between 2010 and 2012.

It did find a few areas of improvement but warned that overall, Italy has one of the slowest judicial systems in Europe. Critics complain that is partly due to reforms implemented by previous Berlusconi governments, and Italian President Giorgio Napolitano has said that the country's judiciary has too often been "overwhelmed" by political disputes that have gone on for "far too long".

Even with the "unequivocal respect" the judiciary is entitled to according to the Italian Constitution, said Napolitano, it has been too often "swept up in the spiral of conflicts between politics and justice that has been raging for too many years in Italy".

Streamlining and speeding processes in the judicial system, a significant issue that has discouraged multinational firms from investing in Italy, is one of the priorities of Premier Matteo Renzi's government.

Renzi's ruling Democratic Party has insisted the former premier cannot be considered above the law.

Meanwhile, Berlusconi's FI party insists he should be entitled to stand in the European Parliament elections despite his tax-fraud conviction.

Some supporters have even suggested the ban should be lifted by Napolitano, although Berlusconi has ruled out asking for a pardon because that would be an admission of guilt. At the same time, Berlusconi remains ensnared in numerous judicial actions.

Next month, Italian judges are set to rule on whether the media magnate, whose four-year sentence was later commuted to one year, should serve that under house arrest or doing community service. And in two separate cases, Berlusconi is appealing a seven-year term for paying an underage prostitute for sex and a one-year sentence for involvement in the publication of an illegally obtained wiretap that hurt a left-wing rival.

The charismatic conservative leader is also on trial for allegedly bribing a Senator to switch sides.

Most of Berlusconi's previous judicial cases have timed out which is why his conviction last fall came as a surprise to many. It also illustrates the problem with Italy's very slow-moving judicial system, highlighted in Monday's EC report.

While it took an average 500 days for civil and commercial cases to reach a first-instance ruling in 2010, that rose to 600 days in 2012, the EC said in its "Justice Scorecard".

It concluded that Italy is one of the slowest countries in the European Union in terms of the number of outstanding civil and commercial court cases waiting for their day in court.

Based on 2012 figures, 5.5 cases were pending per hundred Italians, down from 2010 figures of six outstanding cases per hundred inhabitants, according to the EU assessment. The average length of wait for judicial action on a case in 2012 was about 600 days - up from about 500 days in 2010, the report said. "Justice delayed is justice denied," said justice commissioner Reding.

"The EU Justice Scoreboard is a key tool within the EU's economic strategy, enabling more effective justice for citizens and businesses," she added.

"A properly functioning, independent justice system is essential to gaining the trust of citizens and investors, and indispensable for mutual trust in the European area of justice".

In terms of perceived judicial independence, Italy ranked 20th of 28 states, but was sixth from the top on measurements of ongoing training for workers in the justice system.