A row has developed over the appearance at the European Parliament next week of Facebook founder Mark Zuckerberg.
Mr Zuckerberg has accepted a request by MEPs to appear before them next Tuesday afternoon in Brussels.
However, the meeting will not be held in public. Instead, it will be a closed session with the leaders of each of the eight political factions that make up the European Parliament.
Announcing the appearance, the Parliament's President Antonio Tajani said: "The Conference of Presidents has agreed that Mark Zuckerberg should come to clarify issues related to the use of personal data.
"The founder and CEO of Facebook has accepted our invitation and… will meet the leaders of the political groups and the chair and Rapporteur of the Committee of Civil Liberties, Justice and Home Affairs."
Within minutes of the announcement, Guy Verhofstadt MEP, who leads the Alliance of Liberals and Democrats for Europe (ALDE), said he would not attend.
He tweeted: "I will not attend the meeting with Mr Zuckerberg if it's held behind closed doors. It must be a public hearing – why not a Facebook Live?"
Left-leaning political groupings all criticised the closed appearance. They had called for a similar format to that which was used for Mr Zuckerberg's public and televised appearance in front of the US Congress in April.
However, calls for Mr Zuckerberg to appear publicly in front of the Parliament's Civil Liberties Committee were rejected in favour of the Conference of Presidents format.
The European Commissioner for Justice, Consumers and Gender Equality, Vera Jourova, criticised the move.
She tweeted: "Glad that Mark Zuckerberg accepted invitation from @Europarl_EN and will come to Brussels to answer European questions on privacy. Pity this will not be a public hearing.
"There are more EU users on FB than there are in the US & Europeans deserve to know how their data is handled."
Responding to her, Antonio Tajani, the President of the Parliament wrote: "This is a decision of the Conference of Presidents. It is not your job to control and criticize the @Europarl_EN."
The chosen format means that there will be no cameras allowed in the session although a transcript will be provided afterwards.
All but two of the members of the Conference of Presidents are men and, as group leaders, none had a direct or particular focus on technology or civil liberties. Their average age is 54.
Syed Kamall, leader of the Conservative ECR grouping, who did not object to the closed hearing, said he was concerned about a "witch hunt" against Facebook.
He added: "I am pleased Mr Zuckerberg has agreed to meet MEPs. This will be a good opportunity for him to demonstrate that Facebook understand our concerns and show they're protecting data and applying EU rules and standards.
"The meeting should be about providing real answers and educating the public, but I am concerned that some in the parliament will want to turn this issue into a witch hunt of large companies, which doesn't benefit anyone."
Former UKIP leader Nigel Farage is eligible to attend meeting because he leads the right wing EFDD grouping. He had asked the Parliament President for an "open format" but didn't reject the closed session.
Politicians across Europe have been keen to question the Facebook chief executive regarding the improper use of 87 million users' data by British firm Cambridge Analytica.
Facebook has already admitted that 2.7 million people in the EU could have been affected by the data-sharing scandal.
More than a million of these victims are believed to be in the UK, but Mr Zuckerberg has so far refused to appear before British MPs, in a move they have describe as "absolutely astonishing".
The latest correspondence between Facebook and the British Parliament is a 40-page letter from Facebook UK's head of public policy Rebecca Stimson, in which the company provides answers to questions raised by the Digital, Culture, Media and Sport Committee.
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However the letter closes by rejecting the invitation for Mr Zuckerberg to appear in Parliament, and says: "While Mr Zuckerberg has no plans to meet with the committee or travel to the UK at the present time, we continue to fully recognise the seriousness of these issues and remain committed to working with you."
Mr Zuckerberg's closed session at the European Parliament is scheduled for 5.45pm (4.45pm UK time) on Tuesday.