KIEV, Jan 23 (AFP) - Pro-Western reformer Viktor Yushchenko was sworn in as the third president of an independent post-Soviet Ukraine on Sunday, capping a tumultuous campaign.
Here is a brief rundown of how the crisis, which roiled the nation and sparked Cold War-like exchanges between Russia and the West, unfolded.

Sept 6 2004: Yushchenko falls ill with mysterious pains and is rushed in critical condition four days later to the Rudolfinerhaus private clinic in Vienna, where he remains until September 19 when he emerges with a grotesquely disfigured face. After months of tests, the doctors will pronounce the illness a result of massive dioxin poisoning, which the opposition leader insists is the work of his political opponents.

Oct 31: Yushchenko narrowly edges out his pro-Russia electoral rival, Prime Minister Viktor Yanukovich in the first round of the presidential election as international observers report "serious irregularities" in the poll.

Nov 21: The crucial runoff vote takes place, with exit polls showing Yushchenko comfortably ahead.

Nov 22: Early ballot counts show Yanukovich with more than 49 percent of the vote and Yushchenko with nearly 47 percent.
- OSCE observers say the vote falls short of democratic standards.
- European foreign ministers warn Kiev of the consequences to diplomatic relations of recognising the vote, while Russian President Vladimir Putin congratulates Yanukovich on his "convincing" victory.

Nov 23: An estimated 100,000 opposition supporters occupy Kiev's central Independence Square as the same number are mobilised in westrn Lviv, with demonstrations continuing over several days.

Nov 24: Yanukovich is officially proclaimed the winner by the central electoral commission. Yushchenko calls for a general strike.

Nov 25: The supreme court delays publication of the results and Polish Nobel peace prize winner Lech Walesa visits Kiev to mediate in the dispute.
- Dutch Prime Minister Jan Peter Balkenende, whose country holds the rotating EU presidency, tells outgoing President Leonid Kuchma the election results are unacceptable.

Nov 26: Yanukovich tells supporters he will not allow the opposition to "overthrow the constitution" and calls for calm, saying he does not want the presidency if it "provokes bloodshed."
- Yanukovich and Yushchenko sit down at the same table for the first time in the presence of top European and Russian mediators.

Nov 27: In the largest pro-Yanukovich rally to date, some 100,000 people mass in the eastern city of Donetsk, where authorities warn that they will seek more autonomy if Yushchenko becomes president.

Dec 1: Kuchma proposes holding a completely new presidential election, instead of a fresh runoff vote. Parliament dismisses Yanukovich's government with a no-confidence vote.

Dec 2: Kuchma flies to Moscow to meet Putin as the opposition demands that the government "urgently" enacts changes to the electoral law to set a date for holding a rerun.

Dec 3: In a stunning and unexpected ruling, the supreme court annuls the November second-round vote due to massive fraud and sets a new runoff ballot for December 26.

Dec 8: Yushchenko and Kuchma strike a deal to end their standoff as parliament votes in a new central election commission as part of a compromise and the opposition calls off its blockade of government buildings.

Dec 9: NATO and Russia issue a joint call for free and fair elections in what NATO's chief hails as "a major breakthrough" in defusing tension between the West and Moscow.

Dec 25: Ukraine's constitutional court strikes down a section of electoral changes aimed at preventing fraud during the rerun vote that were passed as part of a compromise on December 8. The opposition welcomes the ruling, as it leaves most of the legislation intact and closes the door for any post-election challenges over the legitimacy of the vote.

Dec 26: Ukrainians vote in rerun election.

Dec 27: The central election commission publishes results that show Yushchenko winning with 52 percent of the vote, a difference of more than 2.2 million votes. Yanukovich vows to appeal the poll with the supreme court.

Dec 31: Yanukovich resigns as prime minister, admits his supreme court appeals over the vote are unlikely to be granted.

Jan 10: The central election commission declares Yushchenko the official winner of the rerun vote. Yanukovich finals his final appeal with the high court.

Jan 20: The supreme court throws out Yanukovich's final appeal, parliament sets a date for his inauguration three days later.

01/23/2005 11:27 GMT - AFP