Humanist Professor Richard Dawkins has welcomed the posthumous royal pardon granted to gay scientist Alan Turing and says it will “send a signal to the world which needs to be sent”.

Professor Dawkins joined the campaign to pardon Turing in 2009. At the time he said that Turing could have lived much longer had it not been for religion-influenced laws on homosexuality.

On Tuesday, the author of The God Delusion, who presented a television programme for Channel 4 on Turing, said the impact of the mathematician’s war work could not be overstated. “Turing arguably made a greater contribution to defeating the Nazis than Eisenhower or Churchill. Thanks to Turing and his ‘Ultra’ colleagues at Bletchley Park, Allied generals in the field were consistently, over long periods of the war, privy to detailed German plans before the German generals had time to implement them.

“After the war, when Turing’s role was no longer top-secret, he should have been knighted and fêted as a saviour of his nation. Instead, this gentle, stammering, eccentric genius was destroyed, for a ‘crime’, committed in private, which harmed nobody,” he said.

Professor Dawkins also called for a permanent financial endowment to support Bletchley Park, where Turing helped break the Nazi Enigma code.

Turing was given a posthumous royal pardon by the Queen on Monday evening.

It addresses his 1952 conviction for homosexuality for which he was punished by being chemically castrated.

The conviction meant he lost his security clearance and had to stop the code-cracking work that had proved vital to the Allies in World War Two.

The pardon was granted under the Royal Prerogative of Mercy after a request by Justice Secretary Chris Grayling.

The UK gay humanist charity the Pink Triangle Trust (PTT) also welcomed news of the pardon.

PTT Secretary George Broadhead said: “It was great to have such a prominent atheist and Humanist as Richard Dawkins supporting the campaign for Turing to be pardoned and it is significant that he identified religious-influenced laws as being to blame for Turing’s suicide.

“As a gay atheist Alan Turing is a Humanist hero and a pardon is long overdue. However, I agree with other LGBT activists that it’s wrong that the many other men convicted of exactly the same offence are not even being given an apology, let alone a pardon.”

Turing died in June 1954 from cyanide poisoning and an inquest decided that he had committed suicide. However, biographers, friends and other students of his life dispute the finding and suggest his death was an accident.

Writing for PinkNews.co.uk, LGBT rights campaigner Chris Ward welcomed the decision to pardon Turing, but said the state still has not formally acknowledged that it was wrong to have persecuted him for his sexuality in the first place.

Campaigners say the pardon should be extended to more than 50,000 men convicted of homosexuality.

In the leadup to the 2010 general election,  David Cameron announced on PinkNews that if he became Prime Minister, he would disregard the convictions of those convicted of historical gay sex offences. The measure was passed by the Coalition government but only applies to the convictions of those who are still alive, not people like Turing who have since died.