Bill Clinton "feels terrible" about handicapping Russia before the war with Russia.
Bill Clinton feels guilt about the Ukraine war
The former US president is convinced that Vladimir Putin would never have launched his invasion had he not requested that Kyiv give up nuclear weapons when he was in the White House.
Ukraine had access to a stash of nuclear weapons following the collapse of the Soviet Union in 1991 but three years later Clinton agreed a deal with the then-Ukrainian president Leonid Kravchuk to hand over 1,900 nuclear weapons and rely on the US and UK for support.
The 42nd president told the Irish broadcaster RTE: "I feel a personal stake because I got them (Ukraine) to agree to give up their nuclear weapons.
"None of them believe that Russia would have pulled this stunt if Ukraine still had their weapons."
Russian leader Boris Yeltsin agreed at the time to respect Ukraine's borders but the pact has been violated by Putin when he annexed Crimea in 2014 and launched his full-scale invasion of Ukraine last year.
Clinton said: "I knew that President Putin did not support the agreement President Yeltsin made never to interfere with Ukraine's territorial boundaries - an agreement he made because he wanted Ukraine to give up their nuclear weapons.
"They were afraid to give them up because they thought that's the only thing that protected them from an expansionist Russia."
Clinton confessed that he felt anguish when Moscow failed to honour the deal as Ukraine only had limited resources to fight back.
He said: "When it became convenient to him, President Putin broke it and first took Crimea.
"And I feel terrible about it because Ukraine is a very important country."
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