The twin atomic pacts, along with an American promise to pay dollars 12bn (pounds 8bn) over the next 20 years for enriched uranium from dismantled Soviet weapons, came at the end of a two-day Russo-American summit joined in its final stage by Leonid Kravchuk, the President of Ukraine.
'We have got together this day to put the last full stop to the last problem of the Cold War,' President Yeltsin declared after Mr Kravchuk signed a nuclear accord bitterly contested by many in Kiev. Under the deal, Ukraine will give up all its approximately 1,700 warheads in return for financial compensation and promises of Western loans, aid and investment. Mr Yeltin referred to some 'differences' with Washington, particularly on the question of possible air strikes against Serbian positions. But the biggest row was between Mr Kravchuk and fellow Ukrainians.
In Kiev, Vyacheslav Chornovil, leader of the Ukrainian nationalist movement, Rukh, condemned the Moscow pact as a 'shameful surrender'. The US and Russia, he said, had 'joined forces to bring Ukraine to its knees'. The Socialist Party leader, Alexander Moroz, suggested parliament might veto it: 'Ukraine gains nothing from this.'
For Mr Yeltsin too, the real crisis is at home. While the summit ended with sedate pomp and promises of partnership, only a mile away, at the other end of Moscow's Novy Arbat, neo-fascist and Communist deputies again flexed their muscles in the State Duma, the lower chamber of Russia's new parliament. Vladimir Zhirinovsky got into a fist fight in the canteen and a Communist, Ivan Rybkin, was elected as speaker.
At a joint press conference, Mr Yeltsin played down the setback to reform, saying that the 12 December election had produced an upper house in tune with the 'line of the President and government' and a Duma that 'will gradually come round to this'. He said: 'I disagree that the first pancake is bad.' Mr Yeltsin vowed 'expanded reform' but in the same breath stressed that it must be 'more socially orientated', a phrase previously used as code for slowing or blocking change by conservatives. Mr Yeltsin also vowed to defend the 'human rights' of Russians in the Baltics, a favourite theme of nationalists.
The Moscow summit also allowed Mr Clinton to escape his own domestic travails caused by the Whitewater property scandal. He stuck firmly to his administration's unstinting support for Mr Yeltsin, despite the growing unease of some Russian reformers over the shape of a new cabinet, due to be announced next week, and concern among Russia's neighbours about Mr Yeltsin's drift into more nationalistic themes. He offered no new money beyond the enriched- uranium contract but did promise to unblock what he said was dollars 2bn due to Russia in the next two years.
Both sides preferred to talk about security, not economics. As part of the so-called Moscow Declaration signed in the Kremlin's Vladimir Hall, Russian and US military commands will change target settings on nuclear missiles by 30 May, so that 'no country will be targeted by the stratetic forces of either side'.
It is largely symbolic and impossible to verify but, in the words of an American statement, does mark the 'first time since the earliest days of the nuclear age the two countries will no longer operate nuclear forces, day-to-day, in a manner that presumes they are enemies'.
Speaking of Ukraine's pledge to rid itself of nuclear weapons entirely, Mr Kravchuk avoided hyperbole and said: 'I think that after examining these documents and realising Ukraine's interest, parliament will support it.'
Ukraine has committed itself to becoming a non-nuclear state at least twice before, in 1991 when it signed the so-called Lisbon Protocol and promised to join the nuclear Non-Proliferation Treaty as a non-nuclear state, and in August last year, when Mr Kravchuk met Mr Yeltsin at Massandra.