The High Court has asked the Court of Justice of the European Union to determine 11 questions about the way data is transferred between the EU and countries outside the bloc, particularly the US.

The case, which was taken by the Data Protection Commissioner, arises from a complaint by an Austrian lawyer, Max Schrems, who said his data privacy rights were breached by the transfer of his personal data by Facebook's European Headquarters in Ireland to its US parent company.

Last October the court ruled it should refer issues relating to the validity of European Commission decisions approving EU-US data transfer channels to the CJEU.

Ms Justice Caroline Costello set out the questions in her formal request to the CJEU for a preliminary ruling.

Among the significant questions to be determined by the European Court, are whether the High Court has correctly found that there is "mass indiscriminate processing" of data by US government agencies under the PRISM and Upstream programmes authorised there.

The court has also referred a question asking if EU law applies to the processing of personal data for national security purposes regardless as to whether that processing takes place in the EU, US or another country outside the EU.

Other questions relate to whether or not there is adequate protection in the US for EU citizens whose data is transferred there, and the extent of a data protection authority's power to suspend the transfer of data, if it considers a third country is subject to surveillance laws conflicting with EU law.

Lawyers for Facebook asked for time to consider whether or not the company would appeal the decision to make a reference to the CJEU.

Lawyers for the Data Protection Commissioner, said it was not clear that there was any entitlement to appeal a High Court decision to direct a reference.

Ms Justice Costello said she would give Facebook until 30 April.

US law allows personal data to be accessed and processed by state agencies in the interests of national security.

The data of citizens in the EU, is much more stringently protected under the Charter of Fundamental Rights.

Ms Justice Costello agreed to make the referral in October, finding that the Data Protection Commissioner had raised well founded concerns that there was an absence of an effective remedy in US law, compatible with the Charter, for EU citizens whose data is transferred to the US, where it is at risk of being accessed and processed by US state agencies.

She agreed there were grounds for believing the EC decisions approving data transfer channels known as Standard Contractual Clauses were invalid.