The editor of The Guardian newspaper is to be grilled by British MPs over the publication of information contained in top-secret documents leaked by US whistleblower Edward Snowden.
The fallout from the publication has caused tensions between various governments, including Australia and Indonesia.
Alan Rusbridger, who has been editor of The Guardian since 1995, will face questions on Tuesday from the Home Affairs Select Committee.
Rusbridger, 59, and The Guardian have faced criticism for publishing details of the activities of the UK's listening post GCHQ and its US counterpart the National Security Agency (NSA).
The revelations were disclosed by former NSA contractor Mr Snowden to The Guardian and other newspapers worldwide including The Washington Post and Germany's Der Spiegel.
Critics, including the heads of GCHQ, MI5 and MI6, have claimed Mr Rusbridger's decision to publish has aided terrorists, while others believe the move may be illegal.
However, champions of the newspaper have hailed its positive influence on public debate around the reach and powers of the security services and intelligence agencies.
The newspaper was named Independent Voice of the Year at human rights campaigners Liberty's annual awards ceremony last month.
"Whatever your position on blanket surveillance, the people and their parliament have a right to debate it and there can be no debate about what we do not know," Shami Chakrabarti, director of Liberty, said.
Among the revelations contained within the NSA files leaked by Snowden were claims that intelligence agents track global leaders' phone calls.
This caused a rift between Australia and Indonesia after it was revealed Australia had tapped the phones of Indonesian President Susilo Bambang Yudhunoyo and his wife, among others.
The revelation also added to diplomatic tensions between the US and its allies, after it was claimed that the phone of German Chancellor Angela Merkel was tapped for 10 years.
