Boris Yeltsin, who played a key role in the Soviet Union's demise and became
Mr Yeltsin - who had a history of heart trouble - died of heart failure in hospital at 1545 (1145 GMT).
He came to power after being promoted by former Soviet leader Mikhail Gorbachev, a man he then outmaneuvered.
He won international acclaim as a defender of democracy when in August 1991 he mounted a tank in
In what became one of the defining moments of his career, Mr Yeltsin rallied the people against an attempt to overthrow Mr Gorbachev's era of glasnost and perestroika.
In another episode of high drama, two years later he ordered Russian tanks to fire on their own parliament in October 1993, when the building was occupied by hardliner political opponents.
But Mr Yeltsin, who became
Bouts of ill-health were accompanied by rumours of a drinking problem, exhibited most famously when Mr Yeltsin grabbed a conductor's baton in Berlin and, apparently inebriated, tried to sing along with the orchestra.
The BBC's diplomatic correspondent Bridget Kendall says despite his unpredictability, Boris Yeltsin remained a reliable Western ally, even when relations grew icy over Nato's military action against
He announced his retirement in the final hours of 1999, handing over to secret service chief Vladimir Putin.
Mr Yeltsin may have disappointed Russians by bringing them neither peace nor prosperity, our correspondent says.
But, she adds, he did help end 70 years of Soviet Communism, and that, in the long run, is what he will probably be remembered for.
Mr Gorbachev paid a mixed tribute to his successor, saying Mr Yeltsin was responsible for "many great deeds for the good of the country and serious mistakes",
Mr Putin has telephoned Mr Yeltsin's widow, Naina, to express his condolences.
The US White House praised Mr Yeltsin as an "historic figure during a time of great change and challenge for
A funeral for the former Russian president will take place at
President Putin has also declared that a day of national mourning.
"We will do everything we can to ensure that the memory of Boris Nikolayevich Yeltsin, his noble thoughts and his words ''take care of
Chechen debacle
Mr Yeltsin's eight years in power brought immense changes to
He banned the Communist Party, introduced a new constitution which concentrated all real power in the hands of the president, and presided over
The BBC's Russian affairs analyst, Steven Eke, says under the Yeltsin leadership, Russians were given greater political and civic freedoms than they had ever enjoyed.
The media, especially television, were able to criticize the authorities, even the president, in a way they would no longer consider possible, he says.
But history may judge Mr Yeltsin's actions towards the rebellious region of
In 1994, Mr Yeltsin launched a disastrous large-scale military intervention in the breakaway republic, pledging to crush resistance in days.
Instead, a bloody war of attrition ensued, which left tens of thousands of people dead, and the north
Speaking in an interview with Russian television in 2000, Mr Yeltsin said that he saw the lives lost in
But he added that there had been no alternative and that
"I cannot shift the blame for
Photo caption
Boris Yeltsin