Whistle-blower Edward Snowden's birthday greeting for jailed leaker Chelsea Manning

From one whistle-blower in exile to another in a military prison comes a birthday greeting. Edward Snowden marked the 27th birthday of Chelsea Manning yesterday with a personalised message that praises the WikiLeaks source for having "inspired an angry public".

Since he astounded the world with his revelations about the US National Security Agency in June last year, Snowden's name has perhaps inevitably been associated with that of Manning who similarly astounded the globe with the WikiLeaks trove of state secrets three years previously. In the pantheon of contemporary US official leakers, Snowden and Manning rank supreme - they were jointly nominated for the Nobel Peace Prize and Snowden has referred to Manning as "a classic whistle-blower".

Now Snowden has offered words of comfort for Manning as she marks her fifth birthday behind bars. From his own exile in Russia, the former NSA contractor thanked Manning for her "extraordinary act of service", regretting that "it has come with such an unbelievable personal cost".

He wrote: "You have inspired an angry public to demand a government that is accountable for its perpetration of torture and other war crimes, for the true costs of its wars, and for conspiring in corruption."

Snowden's greetings are among a slew of birthday messages from artists, writers and activists published by The Guardian newspaper.