Ukraine's opposition leader Viktor Yanukovich has claimed victory in the country's presidential run-off vote, while rival Yulia Tymoshenko has refused to concede.
With almost 80 percent of votes counted, Yanukovich so far has a narrow lead of nearly four percentage points over Prime Minister Yulia Tymoshenko, who is trailing with 45.87 percent of the ballot, the election commission said Monday.
However, Tymoshenko's camp has rejected the results, saying their "parallel count" sees them edging out their pro-Russian rival by 0.8 percent.
Even though the controversial vote has been monitored by 500 international observers, both candidates have accused each other of plotting to rig the vote.
Earlier in the day Yanukovich claimed victory and called on Tymoshenko, 49, to resign as prime minister.
"I think that Yulia Tymoshenko should prepare to resign. She understands that well," Yanukovich said in a television interview.
But looking stern before reporters, the co-architect of the 2004 Orange Revolution, urged her team to "fight for every result, every document and every vote."
She however stopped short of repeating her last week's threat that she'll "rally people" if she loses the race.
The bitterly contested presidential election resembles the October 2004 election in which fraud allegations triggered the Orange Revolution, leading to the cancelation of Yanukovich's official victory.
A re-run vote then propelled Tymoshenko and her then-ally President Viktor Yushchenko to power.