Opposition leader Viktor Yushchenkowill be sworn in as the third president of Ukraine on Sunday.

The following is a brief rundown of major events of the tumultuous presidential election campaign which roiled the nation and drew wide international attention.

-- Oct. 31, 2004: Yushchenko narrowly edges out his pro-Russia electoral rival, Prime Minister Viktor Yanukovych, 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 ahead.

-- Nov. 22: Early ballot counts show Yanukovych with more than 49 percent of the vote and Yushchenko with nearly 47 percent.

-- Organization for Security and Cooperation in Europe (OSCE) observers say the vote falls short of democratic standards.

-- European foreign ministers warn Kiev of the consequences on diplomatic relations, while Russian President Vladimir Putin congratulates Yanukovych on his "convincing" victory.

-- Nov. 23: About 100,000 opposition supporters occupy Kiev's central Independence Square as the same number are mobilized in western Lviv, with demonstrations continuing over several days.

-- Nov. 24: Yanukovych 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 resultsand Polish Nobel peace prize winner Lech Walesa visits Kiev to mediate in the dispute.

-- Nov. 26: Yanukovych 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."

-- Yanukovych and Yushchenko sit down at the same table for thefirst time in the presence of top European and Russian mediators.

-- Nov. 27: In the largest pro-Yanukovych rally to date, some 100,000 people gather 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 presidentialelection, instead of a fresh runoff vote. Parliament dismisses Yanukovych's government with a no-confidence vote.

-- 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 Dec. 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. 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 Dec. 8. Theopposition 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. Yanukovych vows to appeal the poll with the supreme court.

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

-- Jan. 10, 2005: The central election commission declares Yushchenko the official winner of the rerun vote. Yanukovych is rejected by the high court in his final appeal.

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