Mordechai Vanunu has said he revealed details of Israel's clandestine nuclear arms programme to prevent a nuclear holocaust.
In an interview for the BBC's This World programme, Mr Vanunu said he "felt it was not about betraying; it was about reporting".
Mordechai Vanunu is widely regarded as a traitor in Israel and spent 18 years in jail following his revelations.
But his supporters call him a "hero of peace".
Send us your comments about Mordechai Vanunu's interview.
Israel's Nuclear Whistleblower was screened on BBC Two on Sunday 30 May at 2245 BST.
This debate is now closed. Read a selection of your comments below.
The following comments reflect the balance of opinion we have received so far.
I prayed with Mordechai when I was in Sydney in 86, but did not realise who I was praying with. I have prayed for him ever since. It was very courageous what Mordechai has done for the furtherance of World Peace. I admire him for this. I pray that he may have a peaceful, happy and secure future as he has paid his debt.
Some people may feel that people have a moral obligation to betray their country for their sake of world peace. In many ways, this is true. However, when a country has on multiple occasions defended itself and survived brutal onslaught by surrounding countries it is a different story. Israel relies on its nuclear secrecy and deterrent to prevent another full scale war and keep regional stability for everyone that depends on it (that includes us westerners!).
Alex, New York
Vanunu was a dissatisfied technician with a chip on his shoulder after being fired from his low level job at the Dimona nuclear facility. He only saw the "light" about revealing Israel's nuclear capabilities when money was offered. Lets ignore all this blabber from the press and obviously biased journalists about him being a courageous "whistleblower"- he's no hero just a sad angry, fired worker who made a huge mistake.
, Revivim, Israel
When the government is breaking the law people civil servant should no longer feel obliged to show loyalty to that government. Nuclear weapons are better used as deterrent weapons because if they used then the consequences are terrible. So if Israel feels so threaten it should make their existence known.
Aris G, Athens Greece
Vanunu is no hero, just a little man who has been used by everyone. The Israeli's to let the Arabs know what they really have, the press for a good Israeli bashing story and the left to keep their faces in the news. Mordechai - wake up they are all using you.
Kenny , Stirling, Scotland
Vanunu's actions did nothing to help world peace but were motivated only by his hatred of his own country and people. One's position on Israel's weapons is strictly decided by one's position on the ongoing conflict, and any attempts to make it seem like Vanunu had some higher moral goal for the sake of humanity is a lie. And I thought he wasn't allowed to talk to foreign journalists.
If Israel has nuclear weapons, good for them! They are taking steps to protect their country against their hostile neighbours and I think Mordechai Vanunu deserved to be imprisoned for undermining Israel's entire defence system.
Graeme Phillips, Berlin, Germany
Of course he was trying to prevent a holocaust. Losing one's job, as he did, must have seemed quite a holocaust that he was determined to prevent at all costs.
Inna Tysoe, Sacramento, California, USA
Please stop referring to Vanunu as a "whistleblower". You are trying to make him out to be a victim. He is just another participant with his own self interested agenda.
What Mr Vanunu did was despicable. He quite blatantly betrayed the trust of his country, and simply expects Israel to just sit by and let him go wherever he pleases. He totally fails to see the consequences of his actions, as is apparent by the simple fact he claims "it wasn't about betraying; it was about reporting" The end result could have severely compromised Israel's security.
Scott Troy, Cincinnati, Ohio
Maybe he betrayed Israel, but he did a service to the rest of the world. It's time people stop thinking in terms of 'my country, my country' and start thinking in terms of 'human beings, human beings'. If people would just stop putting country ahead of people, then the world would be a better place. Award Vanunu a medal.
Mark, Brisbane, Australia
I don't care whether we're talking about Israel, Iraq, Russia or the US; what Vanunu did was right. The nation state is not sacred, and political leaders frequently decide to do things that are unethical or even criminal. Sometimes we have a moral obligation to "betray" our country - and this takes more guts than most people have.
Tom Hunsberger, Canadian in Mexico
Mordechai Vanunu's is a story of the persistence and endurance of the human spirit. What he did to Israel I believe he did with the greatest moral intentions for the rest of the world; but how he kept his spirit and determination and resolve alive through 18 years under such harsh treatment is why I believe he should be so admired; he has never doubted the importance and significance of his actions with The Sunday Times.
Brenda, Armagh, N. Ireland
Iraq was attacked for possessing WMD, which are yet to be found. Israel still possesses WMD and the world is sitting idly by just watching. What a hypocritical world we live in.
It would be interesting to know how much money did he get for trying "to prevent a nuclear holocaust"
Victor, San Gwann, Malta
Israel's clandestine nuclear arms programme is in contravention of the nuclear non-proliferation treaty - yet the world idly stands by and does nothing about it, as it does regarding Israel's illegal occupation of Gaza and the West Bank. Nothing to do with the lobby in America by any chance? Vanunu, like many other Israelis not prepared to follow their country's policies, is a hero. I nominate him for the Nobel Peace Prize.
I do not think there's anything worse than to betray your country. Vanunu betrayed Israel and now he will try to find every possible explanation for this betrayal.
Where were the weapons inspections team then? Why was Israel allowed to develop weapons of mass destruction? These and other questions simply point to the lack of justice and sense of equality that has become the state of the nation of Israel. One would hope that a country that claims to "remember" the past now is doomed to repeat on another repressed population.
Robert Spann, Ann Arbor, USA
He's a hero. Many people who admire brave little Israel are at times disappointed that the end claims to justify the means.
Gary Emond, Cleveland, Ohio USA
Vanunu seems to have changed his tune. He has often shown his contempt for Israel, now he says he "told all" to prevent it from a nuclear holocaust. Maybe those 18 years of justified incarceration have finally taken their toll and he himself is suffering from some kind of "meltdown". As for living in the States, he forgets he was convicted of espionage; laws there prohibit the granting of citizenship to convicted felons. This was obviously not thought of when he decided to "blow the whistle".
David Spenser, Ra'anana, Israel
Any other country would consider him a traitor, yet I have the feeling BBC readers will consider him a hero. Pretend it wasn't about Israel, and then you'd consider him a traitor. Now ask yourself why because it concerns Israel is your opinion different.
I have followed Mordechai Vanunu's case closely, thanks to the BBC, but I have to say that in light of the politics of the Middle East and international politics in general, Vanunu is a naive idealist and a traitor to Israel. I am a pacifist but I have to contend with the realities of the world. The international system is anarchical and while institutional mechanisms such as the UN could held restore order, it is weak and amenable to manipulations by all member states. If Vanunu had reported to the world that Israel was about to launch nuclear warheads on a country without provocation, I would have considered him a hero of peace. But Vanunu disclosed top secrets of huge security implications to Israel.
Zachary A. Lomo, Kampala, Uganda
The road to hell is paved with good intentions. However, traitors can't plead ignorance or 'good intentions.
I think Mr. Vanunu should be awarded by the Israeli government. After all, his disclosure of the Israeli nuclear capabilities served as a deterrent to possible hostile Arab countries' actions.
Vladimir Dvoretzky, Sofia, Bulgaria