The Guardian is set to find out next week whether its revelations of government surveillance, based on leaked material from the whistleblower Edward Snowden, has earnt the title a coveted Pulitzer prize – while senior ministers in the UK have been warned that the leaks have caused severe damage to national security.

The Times reports that the Home Office counter-terrorism chief has passed "detailed material … to the prime minister and colleagues on how individual suspects and suspected terror cells have dropped off the intelligence radar since the publication of information on surveillance capabilities and methods".

The paper reports that Charles Farr, head of the Office for Security and Counter-Terrorism, said "the work of countering the international threat to Britain became ?more challenging and harder? last year because of the Snowden leaks".