Greek MEP Eva Kaili had her powers as a vice president of the European Parliament suspended Saturday over a corruption probe implicating World Cup hosts Qatar.

European Parliament President Roberta Metsola "has decided to suspend with immediate effect all powers, duties and tasks that were delegated to Eva Kaili in her capacity as Vice-President of the European Parliament," a spokesperson said.

Earlier European politicians called on Kaili to resign after she was arrested in a corruption probe implicating a wealthy Gulf state.

Belgian prosecutors suspect the country — identified by several media outlets as World Cup hosts Qatar — has influenced the decisions of the European Parliament through cash payments or gifts to lawmakers in the EU assembly.

Kaili was one of five people detained by Belgian police on Friday — one of the others is a former European lawmaker.

Authorities are due to decide on Sunday whether the five should continue to be held in custody.

What was the reaction to Kaili's arrest?

"I hope this woman has the decency to give back her mandate," Luxembourg Foreign Minister Jean Asselborn told the Sunday edition of the German newspaper Tagesspiegel.

German Green Party MEP Anton Hofreiter told the Redaktionsnetzwerk Deutschland that if the accusations prove to be true, Kaili "must not only withdraw from the [vice] presidency of the EU Parliament but also resign her mandate."

Jens Geier, the chair of the German Social Democratic Party's 16-member delegation in the European Parliament, also called on Kaili to resign immediately, adding: "It can't go on like this for another day."

In Athens, the president of the Greek socialists (PASOK), Nikos Androulakis, announced on Twitter that Kaili had been expelled from the party.

The center-left Socialists and Democrats (S&D) in the European Parliament said Kaili had been suspended from their grouping.

S&D president Iratxe Garcia Perez tweeted on Saturday that they would call for Kaili to be replaced as a parliamentary vice president.

Anti-corruption campaign group Transparency International said the allegations showed that MEPs needed to be held to higher standards.

"This is not an isolated incident," said Transparency director Michiel van Hulten. "While this may be the most egregious case of alleged corruption the European Parliament has seen in many years, it is not an isolated incident."

Van Hulten said the parliament had "become a law until itself" by allowing a culture of impunity to develop over several decades, with a combination of lax financial rules and controls and a complete lack of ethics oversight. 

Who is Eva Kaili and why was she arrested?

Kaili, a former journalist and TV presenter, is one of 14 vice presidents in the European Parliament, representing Greece's socialist PASOK party.

She works as an adviser on foreign policy and human rights issues.

The 44-year-old was arrested by Belgian police on Friday, along with four others, in connection with a suspected influence-peddling investigation.

The five were detained after a series of raids in Brussels which prosecutors said turned up €600,000 ($630,000) in cash. Computers and mobile phones were also seized.

Belgian daily L'Echo reported Saturday that "several bags full of [money] notes" were found at Kaili's Brussels home.

The newspaper said police only decided to search her property after her father was caught carrying a large amount of cash in a suitcase.

Authorities declined to identify the country behind the alleged influence efforts, but several media outlets said the country in question was Qatar, which is currently playing host to the soccer World Cup.

Days before the tournament, Kaili met Qatar's Labor Minister Ali bin Samikh Al Marri and spoke positively about the country's progress in labor reforms.

Qatar has faced sharp criticism over the treatment of foreign labor that has built its impressive World Cup stadia.

Thousands of migrant workers have died in the decade since the country was awarded the tournament by football's world governing body, FIFA.

mm/fb (AFP, AP, dpa)